CVE-2026-74256bpf, sockmap: fix integer overflow in bpf_msg_pop_data() bounds check
- 8.4HighCVSS base score
- 0.18%Exploitation in 30 daysEPSS · top 92% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
In the Linux kernel, the following vulnerability has been resolved: bpf, sockmap: fix integer overflow in bpf_msg_pop_data() bounds check start and len are u32, so u64 last = start + len; evaluates start + len in 32-bit and wraps before storing it in last. The bounds check if (start >= offset + l || last > msg->sg.size) return -EINVAL; can then be passed with an out-of-range start/len, after which the pop loop runs off the end of the scatterlist and sk_msg_shift_left() calls put_page() on the empty msg->sg.end slot: Oops: general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] SMP KASAN PTI KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f] RIP: 0010:sk_msg_shift_left net/core/filter.c:2957 [inline] RIP: 0010:____bpf_msg_pop_data net/core/filter.c:3103 [inline] RIP: 0010:bpf_msg_pop_data+0x753/0x1a10 net/core/filter.c:2984 Call Trace: <TASK> bpf_prog_4cc92c278f4d5d56+0x1b1/0x1e8 bpf_prog_run_pin_on_cpu+0x107/0x320 include/linux/filter.h:746 sk_psock_msg_verdict+0x357/0x7f0 net/core/skmsg.c:934 tcp_bpf_send_verdict net/ipv4/tcp_bpf.c:420 [inline] tcp_bpf_sendmsg+0x766/0x1ae0 net/ipv4/tcp_bpf.c:583 __sock_sendmsg+0x153/0x1c0 net/socket.c:802 __sys_sendto+0x326/0x430 net/socket.c:2265 __x64_sys_sendto+0xe3/0x100 net/socket.c:2268 do_syscall_64+0x14c/0x480 entry_SYSCALL_64_after_hwframe+0x77/0x7f </TASK> Widen the addition with a (u64) cast so the bound is evaluated in 64-bit and a len near U32_MAX no longer wraps below msg->sg.size. While here, change pop from int to u32. It counts bytes against the unsigned scatterlist lengths and can never be negative, so the signed type only invites sign-confusion in the pop loop.
Timeline
ID reserved
By Linux
Published
- 2 months later
· 2 months later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| LinuxCNA (assigner) | 3.1 | High8.4 | CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| NVDNVD · Received | 3.1 | High8.4 | CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 0.18% · top 92% of all CVEs (15 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: total
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 8.4.
Affected products
- affected 7246d8ed4dcce23f7509949a77be15fa9f0e3d28 – < 9ef44ed6fb0c1db01cfcc3de432a33e719713eb5
- affected 7246d8ed4dcce23f7509949a77be15fa9f0e3d28 – < d693c5ed67dabe1ccbf8dcea93075bdc9ffd4ca0
- affected 7246d8ed4dcce23f7509949a77be15fa9f0e3d28 – < ba5cc05dae8fce237d191c7ea96b1107a791e548
- affected 7246d8ed4dcce23f7509949a77be15fa9f0e3d28 – < c05a0ec1cdced622a1a0c7d85679fe02f31033ec
- affected 7246d8ed4dcce23f7509949a77be15fa9f0e3d28 – < 17eb9832a10db2f7a80cb429ca2bc5038445a943
- affected 7246d8ed4dcce23f7509949a77be15fa9f0e3d28 – < fe09dd288722f1c749b7506c0b3e7841a7d85027
- affected 7246d8ed4dcce23f7509949a77be15fa9f0e3d28 – < e09f7bd7273928b4089e6b71f8e992f2b356ca1b
- affected 7246d8ed4dcce23f7509949a77be15fa9f0e3d28 – < a48802fb2cd2d1e23651989f8ff4d15e9d5dad54
- affected 5.0
- unaffected < 5.0
- unaffected 5.10.261 – ≤ 5.10.*
- unaffected 5.15.212 – ≤ 5.15.*
- unaffected 6.1.178 – ≤ 6.1.*
- unaffected 6.6.145 – ≤ 6.6.*
- unaffected 6.12.97 – ≤ 6.12.*
- unaffected 6.18.40 – ≤ 6.18.*
- unaffected 7.1.5 – ≤ 7.1.*
- unaffected 7.2 – ≤ *
References
References8
- https://git.kernel.org/stable/c/9ef44ed6fb0c1db01cfcc3de432a33e719713eb5 (opens in a new tab)
- https://git.kernel.org/stable/c/d693c5ed67dabe1ccbf8dcea93075bdc9ffd4ca0 (opens in a new tab)
- https://git.kernel.org/stable/c/ba5cc05dae8fce237d191c7ea96b1107a791e548 (opens in a new tab)
- https://git.kernel.org/stable/c/c05a0ec1cdced622a1a0c7d85679fe02f31033ec (opens in a new tab)
- https://git.kernel.org/stable/c/17eb9832a10db2f7a80cb429ca2bc5038445a943 (opens in a new tab)
- https://git.kernel.org/stable/c/fe09dd288722f1c749b7506c0b3e7841a7d85027 (opens in a new tab)
- https://git.kernel.org/stable/c/e09f7bd7273928b4089e6b71f8e992f2b356ca1b (opens in a new tab)
- https://git.kernel.org/stable/c/a48802fb2cd2d1e23651989f8ff4d15e9d5dad54 (opens in a new tab)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-59403 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-74256)Record last updated .