CVE-2025-40281sctp: prevent possible shift-out-of-bounds in sctp_transport_update_rto
- —Not scoredno CVSS score yet
- 0.23%Exploitation in 30 daysEPSS · top 86% 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: sctp: prevent possible shift-out-of-bounds in sctp_transport_update_rto syzbot reported a possible shift-out-of-bounds [1] Blamed commit added rto_alpha_max and rto_beta_max set to 1000. It is unclear if some sctp users are setting very large rto_alpha and/or rto_beta. In order to prevent user regression, perform the test at run time. Also add READ_ONCE() annotations as sysctl values can change under us. [1] UBSAN: shift-out-of-bounds in net/sctp/transport.c:509:41 shift exponent 64 is too large for 32-bit type 'unsigned int' CPU: 0 UID: 0 PID: 16704 Comm: syz.2.2320 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Call Trace: <TASK> __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x16c/0x1f0 lib/dump_stack.c:120 ubsan_epilogue lib/ubsan.c:233 [inline] __ubsan_handle_shift_out_of_bounds+0x27f/0x420 lib/ubsan.c:494 sctp_transport_update_rto.cold+0x1c/0x34b net/sctp/transport.c:509 sctp_check_transmitted+0x11c4/0x1c30 net/sctp/outqueue.c:1502 sctp_outq_sack+0x4ef/0x1b20 net/sctp/outqueue.c:1338 sctp_cmd_process_sack net/sctp/sm_sideeffect.c:840 [inline] sctp_cmd_interpreter net/sctp/sm_sideeffect.c:1372 [inline]
Timeline
ID reserved
By Linux
- 8 months later
· 8 months later
Published
- 6 months later
· 6 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
No CVSS score yet: neither the CNA, CISA nor NVD has scored this CVE. NVD status: Deferred.
- EPSS (exploitation in 30 days)
- 0.23% · top 86% of all CVEs (14 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: yes · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Not scored.
Affected products
- affected b58537a1f5629bdc98a8b9dc2051ce0e952f6b4b – < 0e0413e3315199b23ff4aec295e256034cd0a6e4
- affected b58537a1f5629bdc98a8b9dc2051ce0e952f6b4b – < 834e65be429c0fa4f9bb5945064bd57f18ed2187
- affected b58537a1f5629bdc98a8b9dc2051ce0e952f6b4b – < abb086b9a95d0ed3b757ee59964ba3c4e4b2fc1a
- affected b58537a1f5629bdc98a8b9dc2051ce0e952f6b4b – < d0d858652834dcf531342c82a0428170aa7c2675
- affected b58537a1f5629bdc98a8b9dc2051ce0e952f6b4b – < ed71f801249d2350c77a73dca2c03918a15a62fe
- affected b58537a1f5629bdc98a8b9dc2051ce0e952f6b4b – < 1cfa4eac275cc4875755c1303d48a4ddfe507ca8
- affected b58537a1f5629bdc98a8b9dc2051ce0e952f6b4b – < aaba523dd7b6106526c24b1fd9b5fc35e5aaa88d
- affected b58537a1f5629bdc98a8b9dc2051ce0e952f6b4b – < 1534ff77757e44bcc4b98d0196bc5c0052fce5fa
- affected 3.16
- unaffected < 3.16
- unaffected 5.4.302 – ≤ 5.4.*
- unaffected 5.10.247 – ≤ 5.10.*
- unaffected 5.15.197 – ≤ 5.15.*
- unaffected 6.1.159 – ≤ 6.1.*
- unaffected 6.6.117 – ≤ 6.6.*
- unaffected 6.12.59 – ≤ 6.12.*
- unaffected 6.17.9 – ≤ 6.17.*
- unaffected 6.18 – ≤ *
References
References9
- https://git.kernel.org/stable/c/0e0413e3315199b23ff4aec295e256034cd0a6e4 (opens in a new tab)
- https://git.kernel.org/stable/c/834e65be429c0fa4f9bb5945064bd57f18ed2187 (opens in a new tab)
- https://git.kernel.org/stable/c/abb086b9a95d0ed3b757ee59964ba3c4e4b2fc1a (opens in a new tab)
- https://git.kernel.org/stable/c/d0d858652834dcf531342c82a0428170aa7c2675 (opens in a new tab)
- https://git.kernel.org/stable/c/ed71f801249d2350c77a73dca2c03918a15a62fe (opens in a new tab)
- https://git.kernel.org/stable/c/1cfa4eac275cc4875755c1303d48a4ddfe507ca8 (opens in a new tab)
- https://git.kernel.org/stable/c/aaba523dd7b6106526c24b1fd9b5fc35e5aaa88d (opens in a new tab)
- https://git.kernel.org/stable/c/1534ff77757e44bcc4b98d0196bc5c0052fce5fa (opens in a new tab)
- https://cert-portal.siemens.com/productcert/html/ssa-253495.html (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-2025-201574 (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-2025-40281)Record last updated .