CVE-2024-26805 — netlink: Fix kernel-infoleak-after-free in __skb_datagram_iter
In the Linux kernel, the following vulnerability has been resolved: netlink: Fix kernel-infoleak-after-free in __skb_datagram_iter syzbot reported the following uninit-value access issue [1]: netlink_to_full_skb() creates a new `skb` and puts the `skb->data` passed as a 1st arg of netlink_to_full_skb() onto new `skb`. The data size is specified as `len` and passed to skb_put_data(). This `len` is based on `skb->end` that is not data offset but buffer offset. The `skb->end` contains data and tailroom. Since the tailroom is not initialized when the new `skb` created, KMSAN detects uninitialized memory area when copying the data. This patch resolved this issue by correct the len from `skb->end` to `skb->len`, which is the actual data offset. BUG: KMSAN: kernel-infoleak-after-free in instrument_copy_to_user include/linux/instrumented.h:114 [inline] BUG: KMSAN: kernel-infoleak-after-free in copy_to_user_iter lib/iov_iter.c:24 [inline] BUG: KMSAN: kernel-infoleak-after-free in iterate_ubuf include/linux/iov_iter.h:29 [inline] BUG: KMSAN: kernel-infoleak-after-free in iterate_and_advance2 include/linux/iov_iter.h:245 [inline] BUG: KMSAN: kernel-infoleak-after-free in iterate_and_advance include/linux/iov_iter.h:271 [inline] BUG: KMSAN: kernel-infoleak-after-free in _copy_to_iter+0x364/0x2520 lib/iov_iter.c:186 instrument_copy_to_user include/linux/instrumented.h:114 [inline] copy_to_user_iter lib/iov_iter.c:24 [inline] iterate_ubuf include/linux/iov_iter.h:29 [inline] iterate_and_advance2 include/linux/iov_iter.h:245 [inline] iterate_and_advance include/linux/iov_iter.h:271 [inline] _copy_to_iter+0x364/0x2520 lib/iov_iter.c:186 copy_to_iter include/linux/uio.h:197 [inline] simple_copy_to_iter+0x68/0xa0 net/core/datagram.c:532 __skb_datagram_iter+0x123/0xdc0 net/core/datagram.c:420 skb_copy_datagram_iter+0x5c/0x200 net/core/datagram.c:546 skb_copy_datagram_msg include/linux/skbuff.h:3960 [inline] packet_recvmsg+0xd9c/0x2000 net/packet/af_packet.c:3482 sock_recvmsg_nosec net/socket.c:1044 [inline] sock_recvmsg net/socket.c:1066 [inline] sock_read_iter+0x467/0x580 net/socket.c:1136 call_read_iter include/linux/fs.h:2014 [inline] new_sync_read fs/read_write.c:389 [inline] vfs_read+0x8f6/0xe00 fs/read_write.c:470 ksys_read+0x20f/0x4c0 fs/read_write.c:613 __do_sys_read fs/read_write.c:623 [inline] __se_sys_read fs/read_write.c:621 [inline] __x64_sys_read+0x93/0xd0 fs/read_write.c:621 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0x44/0x110 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x63/0x6b Uninit was stored to memory at: skb_put_data include/linux/skbuff.h:2622 [inline] netlink_to_full_skb net/netlink/af_netlink.c:181 [inline] __netlink_deliver_tap_skb net/netlink/af_netlink.c:298 [inline] __netlink_deliver_tap+0x5be/0xc90 net/netlink/af_netlink.c:325 netlink_deliver_tap net/netlink/af_netlink.c:338 [inline] netlink_deliver_tap_kernel net/netlink/af_netlink.c:347 [inline] netlink_unicast_kernel net/netlink/af_netlink.c:1341 [inline] netlink_unicast+0x10f1/0x1250 net/netlink/af_netlink.c:1368 netlink_sendmsg+0x1238/0x13d0 net/netlink/af_netlink.c:1910 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] ____sys_sendmsg+0x9c2/0xd60 net/socket.c:2584 ___sys_sendmsg+0x28d/0x3c0 net/socket.c:2638 __sys_sendmsg net/socket.c:2667 [inline] __do_sys_sendmsg net/socket.c:2676 [inline] __se_sys_sendmsg net/socket.c:2674 [inline] __x64_sys_sendmsg+0x307/0x490 net/socket.c:2674 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0x44/0x110 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x63/0x6b Uninit was created at: free_pages_prepare mm/page_alloc.c:1087 [inline] free_unref_page_prepare+0xb0/0xa40 mm/page_alloc.c:2347 free_unref_page_list+0xeb/0x1100 mm/page_alloc.c:2533 release_pages+0x23d3/0x2410 mm/swap.c:1042 free_pages_and_swap_cache+0xd9/0xf0 mm/swap_state.c:316 tlb_batch_pages ---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 0.2% (30-day exploitation probability)+2
- Technical severity (medium)+3
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 (Debian Debian Linux, 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 |
|---|---|---|---|---|
| Debian | Debian Linux | version 10.0 | Vulnerable | NIST National Vulnerability Database |
| Linux | Linux |
version d38200098e3203ba30ba06ed3f345ec6ca75234c≥ 1853c949646005b5959c483becde86608f548f24 and < f19d1f98e60e68b11fc60839105dd02a30ec0d77≥ 1853c949646005b5959c483becde86608f548f24 and < c71ed29d15b1a1ed6c464f8c3536996963046285≥ 1853c949646005b5959c483becde86608f548f24 and < 0b27bf4c494d61e5663baa34c3edd7ccebf0ea44≥ 1853c949646005b5959c483becde86608f548f24 and < d3ada42e534a83b618bbc1e490d23bf0fdae4736≥ 1853c949646005b5959c483becde86608f548f24 and < 59fc3e3d049e39e7d0d271f20dd5fb47c57faf1d≥ 1853c949646005b5959c483becde86608f548f24 and < 661779e1fcafe1b74b3f3fe8e980c1e207fea1fdversion 92994a5f49d0a81c8643452d5c0a6e8b31d85a61 and 11 moreversion 85aec6328f3346b0718211faad564a3ffa64f60e≥ 1853c949646005b5959c483becde86608f548f24 and < ec343a55b687a452f5e87f3b52bf9f155864df65version 65d48c630ff80a19c39751a4a6d3315f4c3c0280version 62f43b58d2b2c4f0200b9ca2b997f4c484f0272f≥ 3.12.49 and < 3.13≥ 3.14.54 and < 3.15≥ 3.18.23 and < 3.19≥ 4.1.10 and < 4.2≥ 4.2.3 and < 4.3version 4.3≥ 1853c949646005b5959c483becde86608f548f24 and < 9ae51361da43270f4ba0eb924427a07e87e48777 |
Vulnerable | CVE Program (cve.org) e CISA ADP |
| Linux | Linux Kernel |
≥ 5.16 and < 6.1.81≥ 3.12.49 and < 3.13≥ 3.14.54 and < 3.15≥ 3.18.23 and < 3.19≥ 4.1.10 and < 4.2≥ 4.2.3 and < 4.19.309≥ 4.20 and < 5.4.271≥ 5.5 and < 5.10.212 and 9 more≥ 5.11 and < 5.15.151≥ 6.2 and < 6.6.21≥ 6.7 and < 6.7.9version 6.8-rc1version 6.8-rc2version 6.8-rc3version 6.8-rc4version 6.8-rc5version 6.8-rc6 |
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 |
|---|---|---|---|---|---|
| 5.5 | CVSS 3.1 | Medium | 1.8 | 3.6 | nvd@nist.gov via NIST National Vulnerability Database |
| 5.5 | CVSS 3.1 | Medium | — | — | GitHub, Inc. via GitHub Security Advisories |
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/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
- Affected products added · linux/linux kernel, debian/debian linux
- CVSS changed · 5.5
- Source status changed · → Modified
- Record created in this database
- 2024
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 2× References added · Oct 14, 2026 – Oct 14, 2026
- 1× Official description updated · Oct 14, 2026 – Oct 14, 2026
References
14 on the record
- git.kernel.org/stable/c/9ae51361da43270f4ba0eb924427a07e87e48777
- git.kernel.org/stable/c/ec343a55b687a452f5e87f3b52bf9f155864df65
- git.kernel.org/stable/c/f19d1f98e60e68b11fc60839105dd02a30ec0d77
- git.kernel.org/stable/c/661779e1fcafe1b74b3f3fe8e980c1e207fea1fd
- git.kernel.org/stable/c/59fc3e3d049e39e7d0d271f20dd5fb47c57faf1d
- git.kernel.org/stable/c/c71ed29d15b1a1ed6c464f8c3536996963046285
- git.kernel.org/stable/c/d3ada42e534a83b618bbc1e490d23bf0fdae4736
- git.kernel.org/stable/c/0b27bf4c494d61e5663baa34c3edd7ccebf0ea44
- lists.debian.org/debian-lts-announce/2024/06/msg00017.html
- cert-portal.siemens.com/productcert/html/ssa-398330.html
- cert-portal.siemens.com/productcert/html/ssa-613116.html
- lists.debian.org/debian-lts-announce/2024/06/msg00020.html
- github.com/advisories/GHSA-7xpv-78qx-q843
- nvd.nist.gov/vuln/detail/CVE-2024-26805
Elsewhere on this site
Related CVEs (same products)
- Critical CVE-2026-99999 ipv4: validate checksum_start before completing checksum 14h
- Unknown CVE-2026-98432 ipv4: free inet_opt and ireq_opt after an RCU grace period 14h
- 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
- Unknown CVE-2026-98427 net/sched: codel: bound the dropping loop per dequeue call 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-2024-26805 is "netlink: Fix kernel-infoleak-after-free in __skb_datagram_iter", rated Medium. It affects Debian Linux (Debian); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 5.5 describes technical severity. EPSS 0.24% 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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