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Published vulnerabilities with severity, known exploitation and official sources.
CVE-2026-34541
Medium · 5.5
CWE-476 Mar 31, 2026
iccDEV: UB in CIccCombinedConnectionConditions::CIccCombinedConnectionConditions()
iccDEV provides a set of libraries and tools for working with ICC color management profiles. Prior to version 2.3.1.6, a crafted ICC profile can trigger Undefined Behavior (UB) via a null-pointer member call in CIccCombinedConnectionConditions::CIccCombinedConnectionConditions() (reported by UBSan as “member call on null pointer of type CIccTagSpectralViewingConditions”). The issue is reachable when running iccApplyNamedCmm with -PCC using a malformed .icc profile. This issue has been patched in version 2.3.1.6.
CVE-2026-32696
High · 7.5
CWE-476 Mar 30, 2026
NanoMQ HTTP Auth: Missing username/password can trigger a NULL-pointer strlen() in auth_http.c:set_data(), causing a process crash — SIGSEGV, remotely triggerable
NanoMQ MQTT Broker (NanoMQ) is an all-around Edge Messaging Platform. In NanoMQ version 0.24.6, after enabling auth.http_auth (HTTP authentication), when a client connects to the broker using MQTT CONNECT without providing username/password, and the configuration params uses the placeholders %u / %P (e.g., username="%u", password="%P"), the HTTP request construction phase enters auth_http.c:set_data(). This results in calling strlen() on a NULL pointer, causing a SIGSEGV crash. This crash can be triggered remotely, resulting in a denial of service. This issue has been patched in version 0.24.7.
CVE-2026-33996
Medium · 5.5
CWE-476 Mar 27, 2026
LibJWT has NULL/bounds validation in JWK octet and RSA PSS parsing
LibJWT is a C JSON Web Token Library. Starting in version 3.0.0 and prior to version 3.3.0, the JWK parsing for RSA-PSS did not protect against a NULL value when expecting to parse JSON string values. A specially crafted JWK file could exploit this behavior by using integers in places where the code expected a string. This was fixed in v3.3.0. A workaround is available. Users importing keys through a JWK file should not do so from untrusted sources. Use the `jwk2key` tool to check for validity of a JWK file. Likewise, if possible, do not use JWK files with RSA-PSS keys.
CVE-2026-33907
Medium · 6.5
CWE-476 Mar 27, 2026
Ella Core Panics during NAS Authentication Response/Failure with missing IEs
Ella Core is a 5G core designed for private networks. Versions prior to 1.7.0 panic when processing Authentication Response and Authentication Failure NAS message missing IEs. An attacker able to send crafted NAS messages to Ella Core can crash the process, causing service disruption for all connected subscribers. No authentication is required. Version 1.7.0 added IE presence verification to NAS message handling.
CVE-2026-33903
Medium · 6.5
CWE-476 Mar 27, 2026
Ella Core panics when processing a crafted NGAP LocationReport message
Ella Core is a 5G core designed for private networks. Versions prior to 1.7.0 panic when processing a specially crafted NGAP LocationReport message. An attacker able to send crafted NGAP messages to Ella Core can crash the process, causing service disruption for all connected subscribers. Version 1.7.0 adds guards in NGAP Location Report handler.
CVE-2026-0968
Low · 3.1
CWE-476 Mar 26, 2026
Libssh: libssh: denial of service due to malformed sftp message
A flaw was found in libssh in which a malicious SFTP (SSH File Transfer Protocol) server can exploit this by sending a malformed 'longname' field within an `SSH_FXP_NAME` message during a file listing operation. This missing null check can lead to reading beyond allocated memory on the heap. This can cause unexpected behavior or lead to a denial of service (DoS) due to application crashes.
CVE-2026-23398
Medium · 5.5
CWE-476 Mar 26, 2026
icmp: fix NULL pointer dereference in icmp_tag_validation()
In the Linux kernel, the following vulnerability has been resolved:
icmp: fix NULL pointer dereference in icmp_tag_validation()
icmp_tag_validation() unconditionally dereferences the result of
rcu_dereference(inet_protos[proto]) without checking for NULL.
The inet_protos[] array is sparse -- only about 15 of 256 protocol
numbers have registered handlers. When ip_no_pmtu_disc is set to 3
(hardened PMTU mode) and the kernel receives an ICMP Fragmentation
Needed error with a quoted inner IP header containing an unregistered
protocol number, the NULL dereference causes a kernel panic in
softirq context.
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000002: 0000 [#1] SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x0000000000000010-0x0000000000000017]
RIP: 0010:icmp_unreach (net/ipv4/icmp.c:1085 net/ipv4/icmp.c:1143)
Call Trace:
<IRQ>
icmp_rcv (net/ipv4/icmp.c:1527)
ip_protocol_deliver_rcu (net/ipv4/ip_input.c:207)
ip_local_deliver_finish (net/ipv4/ip_input.c:242)
ip_local_deliver (net/ipv4/ip_input.c:262)
ip_rcv (net/ipv4/ip_input.c:573)
__netif_receive_skb_one_core (net/core/dev.c:6164)
process_backlog (net/core/dev.c:6628)
handle_softirqs (kernel/softirq.c:561)
</IRQ>
Add a NULL check before accessing icmp_strict_tag_validation. If the
protocol has no registered handler, return false since it cannot
perform strict tag validation.
CVE-2026-23396
Medium · 5.5
CWE-476 Mar 26, 2026
wifi: mac80211: fix NULL deref in mesh_matches_local()
In the Linux kernel, the following vulnerability has been resolved:
wifi: mac80211: fix NULL deref in mesh_matches_local()
mesh_matches_local() unconditionally dereferences ie->mesh_config to
compare mesh configuration parameters. When called from
mesh_rx_csa_frame(), the parsed action-frame elements may not contain a
Mesh Configuration IE, leaving ie->mesh_config NULL and triggering a
kernel NULL pointer dereference.
The other two callers are already safe:
- ieee80211_mesh_rx_bcn_presp() checks !elems->mesh_config before
calling mesh_matches_local()
- mesh_plink_get_event() is only reached through
mesh_process_plink_frame(), which checks !elems->mesh_config, too
mesh_rx_csa_frame() is the only caller that passes raw parsed elements
to mesh_matches_local() without guarding mesh_config. An adjacent
attacker can exploit this by sending a crafted CSA action frame that
includes a valid Mesh ID IE but omits the Mesh Configuration IE,
crashing the kernel.
The captured crash log:
Oops: general protection fault, probably for non-canonical address ...
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
Workqueue: events_unbound cfg80211_wiphy_work
[...]
Call Trace:
<TASK>
? __pfx_mesh_matches_local (net/mac80211/mesh.c:65)
ieee80211_mesh_rx_queued_mgmt (net/mac80211/mesh.c:1686)
[...]
ieee80211_iface_work (net/mac80211/iface.c:1754 net/mac80211/iface.c:1802)
[...]
cfg80211_wiphy_work (net/wireless/core.c:426)
process_one_work (net/kernel/workqueue.c:3280)
? assign_work (net/kernel/workqueue.c:1219)
worker_thread (net/kernel/workqueue.c:3352)
? __pfx_worker_thread (net/kernel/workqueue.c:3385)
kthread (net/kernel/kthread.c:436)
[...]
ret_from_fork_asm (net/arch/x86/entry/entry_64.S:255)
</TASK>
This patch adds a NULL check for ie->mesh_config at the top of
mesh_matches_local() to return false early when the Mesh Configuration
IE is absent.
CVE-2026-4652
High · 7.5
CWE-476 Mar 26, 2026
Remote denial of service via null pointer dereference
On a system exposing an NVMe/TCP target, a remote client can trigger a kernel panic by sending a CONNECT command for an I/O queue with a bogus or stale CNTLID.
An attacker with network access to the NVMe/TCP target can trigger an unauthenticated Denial of Service condition on the affected machine.
CVE-2026-29785
High · 7.5
CWE-476 Mar 25, 2026
NATS Server panic via malicious compression on leafnode port
NATS-Server is a High-Performance server for NATS.io, a cloud and edge native messaging system. Prior to versions 2.11.14 and 2.12.5, if the nats-server has the "leafnode" configuration enabled (not default), then anyone who can connect can crash the nats-server by triggering a panic. This happens pre-authentication and requires that compression be enabled (which it is, by default, when leafnodes are used). Versions 2.11.14 and 2.12.5 contain a fix. As a workaround, disable compression on the leafnode port.
CVE-2026-23382
Medium · 5.5
CWE-476 Mar 25, 2026
HID: Add HID_CLAIMED_INPUT guards in raw_event callbacks missing them
In the Linux kernel, the following vulnerability has been resolved:
HID: Add HID_CLAIMED_INPUT guards in raw_event callbacks missing them
In commit 2ff5baa9b527 ("HID: appleir: Fix potential NULL dereference at
raw event handle"), we handle the fact that raw event callbacks
can happen even for a HID device that has not been "claimed" causing a
crash if a broken device were attempted to be connected to the system.
Fix up the remaining in-tree HID drivers that forgot to add this same
check to resolve the same issue.
CVE-2026-23381
Medium · 5.5
CWE-476 Mar 25, 2026
net: bridge: fix nd_tbl NULL dereference when IPv6 is disabled
In the Linux kernel, the following vulnerability has been resolved:
net: bridge: fix nd_tbl NULL dereference when IPv6 is disabled
When booting with the 'ipv6.disable=1' parameter, the nd_tbl is never
initialized because inet6_init() exits before ndisc_init() is called
which initializes it. Then, if neigh_suppress is enabled and an ICMPv6
Neighbor Discovery packet reaches the bridge, br_do_suppress_nd() will
dereference ipv6_stub->nd_tbl which is NULL, passing it to
neigh_lookup(). This causes a kernel NULL pointer dereference.
BUG: kernel NULL pointer dereference, address: 0000000000000268
Oops: 0000 [#1] PREEMPT SMP NOPTI
[...]
RIP: 0010:neigh_lookup+0x16/0xe0
[...]
Call Trace:
<IRQ>
? neigh_lookup+0x16/0xe0
br_do_suppress_nd+0x160/0x290 [bridge]
br_handle_frame_finish+0x500/0x620 [bridge]
br_handle_frame+0x353/0x440 [bridge]
__netif_receive_skb_core.constprop.0+0x298/0x1110
__netif_receive_skb_one_core+0x3d/0xa0
process_backlog+0xa0/0x140
__napi_poll+0x2c/0x170
net_rx_action+0x2c4/0x3a0
handle_softirqs+0xd0/0x270
do_softirq+0x3f/0x60
Fix this by replacing IS_ENABLED(IPV6) call with ipv6_mod_enabled() in
the callers. This is in essence disabling NS/NA suppression when IPv6 is
disabled.
CVE-2026-23369
Medium · 5.5
CWE-476 Mar 25, 2026
i2c: i801: Revert "i2c: i801: replace acpi_lock with I2C bus lock"
In the Linux kernel, the following vulnerability has been resolved:
i2c: i801: Revert "i2c: i801: replace acpi_lock with I2C bus lock"
This reverts commit f707d6b9e7c18f669adfdb443906d46cfbaaa0c1.
Under rare circumstances, multiple udev threads can collect i801 device
info on boot and walk i801_acpi_io_handler somewhat concurrently. The
first will note the area is reserved by acpi to prevent further touches.
This ultimately causes the area to be deregistered. The second will
enter i801_acpi_io_handler after the area is unregistered but before a
check can be made that the area is unregistered. i2c_lock_bus relies on
the now unregistered area containing lock_ops to lock the bus. The end
result is a kernel panic on boot with the following backtrace;
[ 14.971872] ioatdma 0000:09:00.2: enabling device (0100 -> 0102)
[ 14.971873] BUG: kernel NULL pointer dereference, address: 0000000000000000
[ 14.971880] #PF: supervisor read access in kernel mode
[ 14.971884] #PF: error_code(0x0000) - not-present page
[ 14.971887] PGD 0 P4D 0
[ 14.971894] Oops: 0000 [#1] PREEMPT SMP PTI
[ 14.971900] CPU: 5 PID: 956 Comm: systemd-udevd Not tainted 5.14.0-611.5.1.el9_7.x86_64 #1
[ 14.971905] Hardware name: XXXXXXXXXXXXXXXXXXXXXXX BIOS 1.20.10.SV91 01/30/2023
[ 14.971908] RIP: 0010:i801_acpi_io_handler+0x2d/0xb0 [i2c_i801]
[ 14.971929] Code: 00 00 49 8b 40 20 41 57 41 56 4d 8b b8 30 04 00 00 49 89 ce 41 55 41 89 d5 41 54 49 89 f4 be 02 00 00 00 55 4c 89 c5 53 89 fb <48> 8b 00 4c 89 c7 e8 18 61 54 e9 80 bd 80 04 00 00 00 75 09 4c 3b
[ 14.971933] RSP: 0018:ffffbaa841483838 EFLAGS: 00010282
[ 14.971938] RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff9685e01ba568
[ 14.971941] RDX: 0000000000000008 RSI: 0000000000000002 RDI: 0000000000000000
[ 14.971944] RBP: ffff9685ca22f028 R08: ffff9685ca22f028 R09: ffff9685ca22f028
[ 14.971948] R10: 000000000000000b R11: 0000000000000580 R12: 0000000000000580
[ 14.971951] R13: 0000000000000008 R14: ffff9685e01ba568 R15: ffff9685c222f000
[ 14.971954] FS: 00007f8287c0ab40(0000) GS:ffff96a47f940000(0000) knlGS:0000000000000000
[ 14.971959] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 14.971963] CR2: 0000000000000000 CR3: 0000000168090001 CR4: 00000000003706f0
[ 14.971966] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 14.971968] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 14.971972] Call Trace:
[ 14.971977] <TASK>
[ 14.971981] ? show_trace_log_lvl+0x1c4/0x2df
[ 14.971994] ? show_trace_log_lvl+0x1c4/0x2df
[ 14.972003] ? acpi_ev_address_space_dispatch+0x16e/0x3c0
[ 14.972014] ? __die_body.cold+0x8/0xd
[ 14.972021] ? page_fault_oops+0x132/0x170
[ 14.972028] ? exc_page_fault+0x61/0x150
[ 14.972036] ? asm_exc_page_fault+0x22/0x30
[ 14.972045] ? i801_acpi_io_handler+0x2d/0xb0 [i2c_i801]
[ 14.972061] acpi_ev_address_space_dispatch+0x16e/0x3c0
[ 14.972069] ? __pfx_i801_acpi_io_handler+0x10/0x10 [i2c_i801]
[ 14.972085] acpi_ex_access_region+0x5b/0xd0
[ 14.972093] acpi_ex_field_datum_io+0x73/0x2e0
[ 14.972100] acpi_ex_read_data_from_field+0x8e/0x230
[ 14.972106] acpi_ex_resolve_node_to_value+0x23d/0x310
[ 14.972114] acpi_ds_evaluate_name_path+0xad/0x110
[ 14.972121] acpi_ds_exec_end_op+0x321/0x510
[ 14.972127] acpi_ps_parse_loop+0xf7/0x680
[ 14.972136] acpi_ps_parse_aml+0x17a/0x3d0
[ 14.972143] acpi_ps_execute_method+0x137/0x270
[ 14.972150] acpi_ns_evaluate+0x1f4/0x2e0
[ 14.972158] acpi_evaluate_object+0x134/0x2f0
[ 14.972164] acpi_evaluate_integer+0x50/0xe0
[ 14.972173] ? vsnprintf+0x24b/0x570
[ 14.972181] acpi_ac_get_state.part.0+0x23/0x70
[ 14.972189] get_ac_property+0x4e/0x60
[ 14.972195] power_supply_show_property+0x90/0x1f0
[ 14.972205] add_prop_uevent+0x29/0x90
[ 14.972213] power_supply_uevent+0x109/0x1d0
[ 14.972222] dev_uevent+0x10e/0x2f0
[ 14.972228] uevent_show+0x8e/0x100
[ 14.972236] dev_attr_show+0x19
---truncated---
CVE-2026-23366
Medium · 5.5
CWE-476 Mar 25, 2026
drm/client: Do not destroy NULL modes
In the Linux kernel, the following vulnerability has been resolved:
drm/client: Do not destroy NULL modes
'modes' in drm_client_modeset_probe may fail to kcalloc. If this
occurs, we jump to 'out', calling modes_destroy on it, which
dereferences it. This may result in a NULL pointer dereference in the
error case. Prevent that.
CVE-2026-23353
Medium · 5.5
CWE-476 Mar 25, 2026
ice: fix crash in ethtool offline loopback test
In the Linux kernel, the following vulnerability has been resolved:
ice: fix crash in ethtool offline loopback test
Since the conversion of ice to page pool, the ethtool loopback test
crashes:
BUG: kernel NULL pointer dereference, address: 000000000000000c
#PF: supervisor write access in kernel mode
#PF: error_code(0x0002) - not-present page
PGD 1100f1067 P4D 0
Oops: Oops: 0002 [#1] SMP NOPTI
CPU: 23 UID: 0 PID: 5904 Comm: ethtool Kdump: loaded Not tainted 6.19.0-0.rc7.260128g1f97d9dcf5364.49.eln154.x86_64 #1 PREEMPT(lazy)
Hardware name: [...]
RIP: 0010:ice_alloc_rx_bufs+0x1cd/0x310 [ice]
Code: 83 6c 24 30 01 66 41 89 47 08 0f 84 c0 00 00 00 41 0f b7 dc 48 8b 44 24 18 48 c1 e3 04 41 bb 00 10 00 00 48 8d 2c 18 8b 04 24 <89> 45 0c 41 8b 4d 00 49 d3 e3 44 3b 5c 24 24 0f 83 ac fe ff ff 44
RSP: 0018:ff7894738aa1f768 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000700 RDI: 0000000000000000
RBP: 0000000000000000 R08: ff16dcae79880200 R09: 0000000000000019
R10: 0000000000000001 R11: 0000000000001000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: ff16dcae6c670000
FS: 00007fcf428850c0(0000) GS:ff16dcb149710000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000000000000c CR3: 0000000121227005 CR4: 0000000000773ef0
PKRU: 55555554
Call Trace:
<TASK>
ice_vsi_cfg_rxq+0xca/0x460 [ice]
ice_vsi_cfg_rxqs+0x54/0x70 [ice]
ice_loopback_test+0xa9/0x520 [ice]
ice_self_test+0x1b9/0x280 [ice]
ethtool_self_test+0xe5/0x200
__dev_ethtool+0x1106/0x1a90
dev_ethtool+0xbe/0x1a0
dev_ioctl+0x258/0x4c0
sock_do_ioctl+0xe3/0x130
__x64_sys_ioctl+0xb9/0x100
do_syscall_64+0x7c/0x700
entry_SYSCALL_64_after_hwframe+0x76/0x7e
[...]
It crashes because we have not initialized libeth for the rx ring.
Fix it by treating ICE_VSI_LB VSIs slightly more like normal PF VSIs and
letting them have a q_vector. It's just a dummy, because the loopback
test does not use interrupts, but it contains a napi struct that can be
passed to libeth_rx_fq_create() called from ice_vsi_cfg_rxq() ->
ice_rxq_pp_create().
CVE-2026-23349
Medium · 5.5
CWE-476 Mar 25, 2026
HID: pidff: Fix condition effect bit clearing
In the Linux kernel, the following vulnerability has been resolved:
HID: pidff: Fix condition effect bit clearing
As reported by MPDarkGuy on discord, NULL pointer dereferences were
happening because not all the conditional effects bits were cleared.
Properly clear all conditional effect bits from ffbit
CVE-2026-23341
Medium · 5.5
CWE-476 Mar 25, 2026
accel/amdxdna: Fix crash when destroying a suspended hardware context
In the Linux kernel, the following vulnerability has been resolved:
accel/amdxdna: Fix crash when destroying a suspended hardware context
If userspace issues an ioctl to destroy a hardware context that has
already been automatically suspended, the driver may crash because the
mailbox channel pointer is NULL for the suspended context.
Fix this by checking the mailbox channel pointer in aie2_destroy_context()
before accessing it.
CVE-2026-23332
Medium · 5.5
CWE-476 Mar 25, 2026
cpufreq: intel_pstate: Fix crash during turbo disable
In the Linux kernel, the following vulnerability has been resolved:
cpufreq: intel_pstate: Fix crash during turbo disable
When the system is booted with kernel command line argument "nosmt" or
"maxcpus" to limit the number of CPUs, disabling turbo via:
echo 1 > /sys/devices/system/cpu/intel_pstate/no_turbo
results in a crash:
PF: supervisor read access in kernel mode
PF: error_code(0x0000) - not-present page
PGD 0 P4D 0
Oops: Oops: 0000 [#1] SMP PTI
...
RIP: 0010:store_no_turbo+0x100/0x1f0
...
This occurs because for_each_possible_cpu() returns CPUs even if they
are not online. For those CPUs, all_cpu_data[] will be NULL. Since
commit 973207ae3d7c ("cpufreq: intel_pstate: Rearrange max frequency
updates handling code"), all_cpu_data[] is dereferenced even for CPUs
which are not online, causing the NULL pointer dereference.
To fix that, pass CPU number to intel_pstate_update_max_freq() and use
all_cpu_data[] for those CPUs for which there is a valid cpufreq policy.
CVE-2026-23328
Medium · 5.5
CWE-476 Mar 25, 2026
accel/amdxdna: Fix NULL pointer dereference of mgmt_chann
In the Linux kernel, the following vulnerability has been resolved:
accel/amdxdna: Fix NULL pointer dereference of mgmt_chann
mgmt_chann may be set to NULL if the firmware returns an unexpected
error in aie2_send_mgmt_msg_wait(). This can later lead to a NULL
pointer dereference in aie2_hw_stop().
Fix this by introducing a dedicated helper to destroy mgmt_chann
and by adding proper NULL checks before accessing it.
CVE-2026-23309
Medium · 5.5
CWE-476 Mar 25, 2026
tracing: Add NULL pointer check to trigger_data_free()
In the Linux kernel, the following vulnerability has been resolved:
tracing: Add NULL pointer check to trigger_data_free()
If trigger_data_alloc() fails and returns NULL, event_hist_trigger_parse()
jumps to the out_free error path. While kfree() safely handles a NULL
pointer, trigger_data_free() does not. This causes a NULL pointer
dereference in trigger_data_free() when evaluating
data->cmd_ops->set_filter.
Fix the problem by adding a NULL pointer check to trigger_data_free().
The problem was found by an experimental code review agent based on
gemini-3.1-pro while reviewing backports into v6.18.y.
CVE-2026-23304
Medium · 5.5
CWE-476 Mar 25, 2026
ipv6: fix NULL pointer deref in ip6_rt_get_dev_rcu()
In the Linux kernel, the following vulnerability has been resolved:
ipv6: fix NULL pointer deref in ip6_rt_get_dev_rcu()
l3mdev_master_dev_rcu() can return NULL when the slave device is being
un-slaved from a VRF. All other callers deal with this, but we lost
the fallback to loopback in ip6_rt_pcpu_alloc() -> ip6_rt_get_dev_rcu()
with commit 4832c30d5458 ("net: ipv6: put host and anycast routes on
device with address").
KASAN: null-ptr-deref in range [0x0000000000000108-0x000000000000010f]
RIP: 0010:ip6_rt_pcpu_alloc (net/ipv6/route.c:1418)
Call Trace:
ip6_pol_route (net/ipv6/route.c:2318)
fib6_rule_lookup (net/ipv6/fib6_rules.c:115)
ip6_route_output_flags (net/ipv6/route.c:2607)
vrf_process_v6_outbound (drivers/net/vrf.c:437)
I was tempted to rework the un-slaving code to clear the flag first
and insert synchronize_rcu() before we remove the upper. But looks like
the explicit fallback to loopback_dev is an established pattern.
And I guess avoiding the synchronize_rcu() is nice, too.
CVE-2026-23300
Medium · 5.5
CWE-476 Mar 25, 2026
net: ipv6: fix panic when IPv4 route references loopback IPv6 nexthop
In the Linux kernel, the following vulnerability has been resolved:
net: ipv6: fix panic when IPv4 route references loopback IPv6 nexthop
When a standalone IPv6 nexthop object is created with a loopback device
(e.g., "ip -6 nexthop add id 100 dev lo"), fib6_nh_init() misclassifies
it as a reject route. This is because nexthop objects have no destination
prefix (fc_dst=::), causing fib6_is_reject() to match any loopback
nexthop. The reject path skips fib_nh_common_init(), leaving
nhc_pcpu_rth_output unallocated. If an IPv4 route later references this
nexthop, __mkroute_output() dereferences NULL nhc_pcpu_rth_output and
panics.
Simplify the check in fib6_nh_init() to only match explicit reject
routes (RTF_REJECT) instead of using fib6_is_reject(). The loopback
promotion heuristic in fib6_is_reject() is handled separately by
ip6_route_info_create_nh(). After this change, the three cases behave
as follows:
1. Explicit reject route ("ip -6 route add unreachable 2001:db8::/64"):
RTF_REJECT is set, enters reject path, skips fib_nh_common_init().
No behavior change.
2. Implicit loopback reject route ("ip -6 route add 2001:db8::/32 dev lo"):
RTF_REJECT is not set, takes normal path, fib_nh_common_init() is
called. ip6_route_info_create_nh() still promotes it to reject
afterward. nhc_pcpu_rth_output is allocated but unused, which is
harmless.
3. Standalone nexthop object ("ip -6 nexthop add id 100 dev lo"):
RTF_REJECT is not set, takes normal path, fib_nh_common_init() is
called. nhc_pcpu_rth_output is properly allocated, fixing the crash
when IPv4 routes reference this nexthop.
CVE-2026-23293
Medium · 5.5
CWE-476 Mar 25, 2026
net: vxlan: fix nd_tbl NULL dereference when IPv6 is disabled
In the Linux kernel, the following vulnerability has been resolved:
net: vxlan: fix nd_tbl NULL dereference when IPv6 is disabled
When booting with the 'ipv6.disable=1' parameter, the nd_tbl is never
initialized because inet6_init() exits before ndisc_init() is called
which initializes it. If an IPv6 packet is injected into the interface,
route_shortcircuit() is called and a NULL pointer dereference happens on
neigh_lookup().
BUG: kernel NULL pointer dereference, address: 0000000000000380
Oops: Oops: 0000 [#1] SMP NOPTI
[...]
RIP: 0010:neigh_lookup+0x20/0x270
[...]
Call Trace:
<TASK>
vxlan_xmit+0x638/0x1ef0 [vxlan]
dev_hard_start_xmit+0x9e/0x2e0
__dev_queue_xmit+0xbee/0x14e0
packet_sendmsg+0x116f/0x1930
__sys_sendto+0x1f5/0x200
__x64_sys_sendto+0x24/0x30
do_syscall_64+0x12f/0x1590
entry_SYSCALL_64_after_hwframe+0x76/0x7e
Fix this by adding an early check on route_shortcircuit() when protocol
is ETH_P_IPV6. Note that ipv6_mod_enabled() cannot be used here because
VXLAN can be built-in even when IPv6 is built as a module.
CVE-2026-23286
Medium · 5.5
CWE-476 Mar 25, 2026
atm: lec: fix null-ptr-deref in lec_arp_clear_vccs
In the Linux kernel, the following vulnerability has been resolved:
atm: lec: fix null-ptr-deref in lec_arp_clear_vccs
syzkaller reported a null-ptr-deref in lec_arp_clear_vccs().
This issue can be easily reproduced using the syzkaller reproducer.
In the ATM LANE (LAN Emulation) module, the same atm_vcc can be shared by
multiple lec_arp_table entries (e.g., via entry->vcc or entry->recv_vcc).
When the underlying VCC is closed, lec_vcc_close() iterates over all
ARP entries and calls lec_arp_clear_vccs() for each matched entry.
For example, when lec_vcc_close() iterates through the hlists in
priv->lec_arp_empty_ones or other ARP tables:
1. In the first iteration, for the first matched ARP entry sharing the VCC,
lec_arp_clear_vccs() frees the associated vpriv (which is vcc->user_back)
and sets vcc->user_back to NULL.
2. In the second iteration, for the next matched ARP entry sharing the same
VCC, lec_arp_clear_vccs() is called again. It obtains a NULL vpriv from
vcc->user_back (via LEC_VCC_PRIV(vcc)) and then attempts to dereference it
via `vcc->pop = vpriv->old_pop`, leading to a null-ptr-deref crash.
Fix this by adding a null check for vpriv before dereferencing
it. If vpriv is already NULL, it means the VCC has been cleared
by a previous call, so we can safely skip the cleanup and just
clear the entry's vcc/recv_vcc pointers.
The entire cleanup block (including vcc_release_async()) is placed inside
the vpriv guard because a NULL vpriv indicates the VCC has already been
fully released by a prior iteration — repeating the teardown would
redundantly set flags and trigger callbacks on an already-closing socket.
The Fixes tag points to the initial commit because the entry->vcc path has
been vulnerable since the original code. The entry->recv_vcc path was later
added by commit 8d9f73c0ad2f ("atm: fix a memory leak of vcc->user_back")
with the same pattern, and both paths are fixed here.
CVE-2026-23285
Medium · 5.5
CWE-476 Mar 25, 2026
drbd: fix null-pointer dereference on local read error
In the Linux kernel, the following vulnerability has been resolved:
drbd: fix null-pointer dereference on local read error
In drbd_request_endio(), READ_COMPLETED_WITH_ERROR is passed to
__req_mod() with a NULL peer_device:
__req_mod(req, what, NULL, &m);
The READ_COMPLETED_WITH_ERROR handler then unconditionally passes this
NULL peer_device to drbd_set_out_of_sync(), which dereferences it,
causing a null-pointer dereference.
Fix this by obtaining the peer_device via first_peer_device(device),
matching how drbd_req_destroy() handles the same situation.