CVE-2024-44987 — ipv6: prevent UAF in ip6_send_skb()
In the Linux kernel, the following vulnerability has been resolved: ipv6: prevent UAF in ip6_send_skb() syzbot reported an UAF in ip6_send_skb() [1] After ip6_local_out() has returned, we no longer can safely dereference rt, unless we hold rcu_read_lock(). A similar issue has been fixed in commit a688caa34beb ("ipv6: take rcu lock in rawv6_send_hdrinc()") Another potential issue in ip6_finish_output2() is handled in a separate patch. [1] BUG: KASAN: slab-use-after-free in ip6_send_skb+0x18d/0x230 net/ipv6/ip6_output.c:1964 Read of size 8 at addr ffff88806dde4858 by task syz.1.380/6530 CPU: 1 UID: 0 PID: 6530 Comm: syz.1.380 Not tainted 6.11.0-rc3-syzkaller-00306-gdf6cbc62cc9b #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Call Trace: <TASK> __dump_stack lib/dump_stack.c:93 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119 print_address_description mm/kasan/report.c:377 [inline] print_report+0x169/0x550 mm/kasan/report.c:488 kasan_report+0x143/0x180 mm/kasan/report.c:601 ip6_send_skb+0x18d/0x230 net/ipv6/ip6_output.c:1964 rawv6_push_pending_frames+0x75c/0x9e0 net/ipv6/raw.c:588 rawv6_sendmsg+0x19c7/0x23c0 net/ipv6/raw.c:926 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x1a6/0x270 net/socket.c:745 sock_write_iter+0x2dd/0x400 net/socket.c:1160 do_iter_readv_writev+0x60a/0x890 vfs_writev+0x37c/0xbb0 fs/read_write.c:971 do_writev+0x1b1/0x350 fs/read_write.c:1018 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f936bf79e79 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f936cd7f038 EFLAGS: 00000246 ORIG_RAX: 0000000000000014 RAX: ffffffffffffffda RBX: 00007f936c115f80 RCX: 00007f936bf79e79 RDX: 0000000000000001 RSI: 0000000020000040 RDI: 0000000000000004 RBP: 00007f936bfe7916 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f936c115f80 R15: 00007fff2860a7a8 </TASK> Allocated by task 6530: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:312 [inline] __kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:338 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook mm/slub.c:3988 [inline] slab_alloc_node mm/slub.c:4037 [inline] kmem_cache_alloc_noprof+0x135/0x2a0 mm/slub.c:4044 dst_alloc+0x12b/0x190 net/core/dst.c:89 ip6_blackhole_route+0x59/0x340 net/ipv6/route.c:2670 make_blackhole net/xfrm/xfrm_policy.c:3120 [inline] xfrm_lookup_route+0xd1/0x1c0 net/xfrm/xfrm_policy.c:3313 ip6_dst_lookup_flow+0x13e/0x180 net/ipv6/ip6_output.c:1257 rawv6_sendmsg+0x1283/0x23c0 net/ipv6/raw.c:898 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x1a6/0x270 net/socket.c:745 ____sys_sendmsg+0x525/0x7d0 net/socket.c:2597 ___sys_sendmsg net/socket.c:2651 [inline] __sys_sendmsg+0x2b0/0x3a0 net/socket.c:2680 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 45: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:579 poison_slab_object+0xe0/0x150 mm/kasan/common.c:240 __kasan_slab_free+0x37/0x60 mm/kasan/common.c:256 kasan_slab_free include/linux/kasan.h:184 [inline] slab_free_hook mm/slub.c:2252 [inline] slab_free mm/slub.c:4473 [inline] kmem_cache_free+0x145/0x350 mm/slub.c:4548 dst_destroy+0x2ac/0x460 net/core/dst.c:124 rcu_do_batch kernel/rcu/tree.c:2569 [inline] rcu_core+0xafd/0x1830 kernel/rcu/tree. ---truncated---
Who exploits it and how urgent it is
A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.
How the score was calculated
- EPSS 0.3% (30-day exploitation probability)+2
- Technical severity (high)+6
The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.
CISA SSVC assessment CISA
Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.
Remediation
Fixes and mitigations documented by the sources — linked to the original advisory.
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
First 24 hours
Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.
- Identify exposed assets running the affected vendor/product/version combinations (Linux Linux, Linux Linux Kernel).
- Apply the fixed version or the patch documented under Remediation.
- Search available logs for exploit probes matching the vulnerability class (memory corruption), errors and authentication anomalies.
Affected scope
Vendor, product and versions as the sources word them.
| Vendor | Product | Versions | Status | Source |
|---|---|---|---|---|
| Linux | Linux |
version 2.6.32≥ 0625491493d9000e4556bf566d205c28c8e7dc4e and < faa389b2fbaaec7fd27a390b4896139f9da662e3≥ 0625491493d9000e4556bf566d205c28c8e7dc4e and < e44bd76dd072756e674f45c5be00153f4ded68b2≥ 0625491493d9000e4556bf566d205c28c8e7dc4e and < af1dde074ee2ed7dd5bdca4e7e8ba17f44e7b011≥ 0625491493d9000e4556bf566d205c28c8e7dc4e and < 9a3e55afa95ed4ac9eda112d4f918af645d72f25≥ 0625491493d9000e4556bf566d205c28c8e7dc4e and < 24e93695b1239fbe4c31e224372be77f82dab69a≥ 0625491493d9000e4556bf566d205c28c8e7dc4e and < cb5880a0de12c7f618d2bdd84e2d985f1e06ed7e≥ 0625491493d9000e4556bf566d205c28c8e7dc4e and < ce2f6cfab2c637d0bd9762104023a15d0ab7c0a8 and 1 more≥ 0625491493d9000e4556bf566d205c28c8e7dc4e and < 571567e0277008459750f0728f246086b2659429 |
Vulnerable | CVE Program (cve.org) e CISA ADP |
| Linux | Linux Kernel |
version 6.11-rc4≥ 2.6.32 and < 4.19.321version 6.11-rc3version 6.11-rc2version 6.11-rc1≥ 6.7 and < 6.10.7≥ 6.2 and < 6.6.48≥ 5.16 and < 6.1.107 and 3 more≥ 5.11 and < 5.15.166≥ 5.5 and < 5.10.225≥ 4.20 and < 5.4.283 |
Vulnerable | NIST National Vulnerability Database |
Attack characteristics
The CVSS vector, decoded. It describes the attack, not your exposure to it.
Every base score collected
Sources score independently and may disagree; each row says who scored it and under which version.
| Score | Version | Severity | Expl. | Impact | Scored by |
|---|---|---|---|---|---|
| 7.8 | CVSS 3.1 | High | 1.8 | 5.9 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 via NIST National Vulnerability Database |
| 7.8 | CVSS 3.1 | High | 1.8 | 5.9 | nvd@nist.gov via NIST National Vulnerability Database |
| 7.8 | CVSS 3.1 | High | — | — | GitHub, Inc. via GitHub Security Advisories |
| 7.8 | CVSS 3.1 | High | — | — | Linux via CVE Program (cve.org) e CISA ADP |
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H (score shown at the top: nvd@nist.gov) Weakness MITRE
Weakness class according to MITRE’s CWE catalog.
Detection
Read off the CVSS vector and the weakness class. Starting points, not tested rules.
- Local/physical vector: focus on endpoint telemetry (EDR) from affected hosts.
- Correlate service crashes/restarts with inbound traffic; repeated crashes may indicate attempts.
Timeline
What happened to this CVE, newest first.
- 2026
- Affected products added · linux/linux
- SSVC assessment updated
- Record published
- Fix documented
- CVSS changed · 7.8
- Source status changed · → Modified
- Record created in this database
- 2024
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 1× References added · Oct 14, 2026 – Oct 14, 2026
- 1× Official description updated · Oct 14, 2026 – Oct 14, 2026
References
15 on the record
- git.kernel.org/stable/c/24e93695b1239fbe4c31e224372be77f82dab69a
- git.kernel.org/stable/c/e44bd76dd072756e674f45c5be00153f4ded68b2
- git.kernel.org/stable/c/faa389b2fbaaec7fd27a390b4896139f9da662e3
- git.kernel.org/stable/c/cb5880a0de12c7f618d2bdd84e2d985f1e06ed7e
- git.kernel.org/stable/c/af1dde074ee2ed7dd5bdca4e7e8ba17f44e7b011
- git.kernel.org/stable/c/571567e0277008459750f0728f246086b2659429
- git.kernel.org/stable/c/9a3e55afa95ed4ac9eda112d4f918af645d72f25
- git.kernel.org/stable/c/ce2f6cfab2c637d0bd9762104023a15d0ab7c0a8
- github.com/advisories/GHSA-wp45-jw6q-jm9q
- cert-portal.siemens.com/productcert/html/ssa-355557.html
- nvd.nist.gov/vuln/detail/CVE-2024-44987
- cert-portal.siemens.com/productcert/html/ssa-613116.html
- cert-portal.siemens.com/productcert/html/ssa-265688.html
- lists.debian.org/debian-lts-announce/2024/10/msg00003.html
- lists.debian.org/debian-lts-announce/2025/01/msg00001.html
Elsewhere on this site
Related CVEs (same products)
- Critical CVE-2026-99999 ipv4: validate checksum_start before completing checksum 13h
- Unknown CVE-2026-98432 ipv4: free inet_opt and ireq_opt after an RCU grace period 13h
- Unknown CVE-2026-98431 RDMA/uverbs: Fix mmap_lock/disassociation_lock circular dependency 1d
- Unknown CVE-2026-98424 wifi: cfg80211: undo netns switch if renaming the wiphy fails 1d
- Unknown CVE-2026-98425 wifi: mac80211: don't warn when an IBSS has no channel to scan 1d
- Unknown CVE-2026-98426 wifi: mwifiex: fix IRQ leak using wrong index in MSI-X error path 1d
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.
Answered from this record
Text assembled only from the fields above — no additional claims.
What should defenders know first?
CVE-2024-44987 is "ipv6: prevent UAF in ip6_send_skb()", rated High. It affects Linux (Linux); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 7.8 describes technical severity. EPSS 0.26% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.
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