CVE-2026-89479sctp: stop processing a packet once its association is deleted
- 9.8CriticalCVSS base score
- 0.50%Exploitation in 30 daysEPSS · top 57% 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: stop processing a packet once its association is deleted sctp_endpoint_bh_rcv() looks the association up only when chunk->asoc is NULL, and caches the result in chunk->asoc and chunk->transport without taking a reference. A packet that matches no association is handed to the endpoint, so a peer can bundle COOKIE ECHO, SHUTDOWN and SHUTDOWN ACK in one packet. The COOKIE ECHO creates the association, the SHUTDOWN chunk caches it, and with the outqueue empty the SHUTDOWN ACK reaches sctp_sf_do_9_2_final(), so the association and its transports are freed. The endpoint loop has no counterpart to the asoc->base.dead check in sctp_assoc_bh_rcv(). The next chunk writes to last_time_heard in the freed transport and is then passed to sctp_do_sm() with the freed association. The transport is freed through RCU, so this needs the packet to come off the socket backlog, where the loop runs in task context. The endpoint loop cannot do the same check: it holds no reference on the association, so reading asoc->base.dead would itself be a use-after-free. Mark the packet for discard in the command interpreter, just before it deletes the association. That is also before sctp_inq_free() releases the chunk on the association receive path. sctp_sf_do_5_2_4_dupcook() issues SCTP_CMD_DELETE_TCB for the temporary association, while the one the packet belongs to stays alive. A restarting peer can bundle DATA behind its COOKIE ECHO, so compare against chunk->asoc and leave that case alone.
Timeline
ID reserved
By Linux
Published
- 38 days later
· 38 days 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 | Critical9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| NVDNVD · Received | 3.1 | Critical9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 0.50% · top 57% of all CVEs (13 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: yes · Technical impact: total
The list uses the assigner's score when there is one, then CISA's, then NVD's: Critical 9.8.
Affected products
- affected 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 – < 7d970353eeb98f46a3b9dc602850e4f6336a9889
- affected 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 – < 09c3b193a3e8fe53e1f416e2f8e3283d2a785405
- affected 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 – < ed85fe91a61bc0e0da6b585c07102b20f4cc65a0
- affected 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 – < 5c0b2dbbdafc9eeeb11fffe1e46551fc3b55d8ee
- affected 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 – < ee3f04cf566f6041aa9a0360494fd8db5ade383a
- affected 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 – < fa306a40e716c5abcd967475459ce1ebd56e5115
- affected 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 – < a713e1b3a265f180ad25a08e17be15d67a2f7149
- affected 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 – < 47e15a8d12e366d0d261bcbc394394f44418938d
- affected 2.6.12
- unaffected < 2.6.12
- unaffected 5.10.270 – ≤ 5.10.*
- unaffected 5.15.221 – ≤ 5.15.*
- unaffected 6.1.188 – ≤ 6.1.*
- unaffected 6.6.157 – ≤ 6.6.*
- unaffected 6.12.109 – ≤ 6.12.*
- unaffected 6.18.50 – ≤ 6.18.*
- unaffected 7.2.4 – ≤ 7.2.*
- unaffected 7.3 – ≤ *
References
References8
- https://git.kernel.org/stable/c/7d970353eeb98f46a3b9dc602850e4f6336a9889 (opens in a new tab)
- https://git.kernel.org/stable/c/09c3b193a3e8fe53e1f416e2f8e3283d2a785405 (opens in a new tab)
- https://git.kernel.org/stable/c/ed85fe91a61bc0e0da6b585c07102b20f4cc65a0 (opens in a new tab)
- https://git.kernel.org/stable/c/5c0b2dbbdafc9eeeb11fffe1e46551fc3b55d8ee (opens in a new tab)
- https://git.kernel.org/stable/c/ee3f04cf566f6041aa9a0360494fd8db5ade383a (opens in a new tab)
- https://git.kernel.org/stable/c/fa306a40e716c5abcd967475459ce1ebd56e5115 (opens in a new tab)
- https://git.kernel.org/stable/c/a713e1b3a265f180ad25a08e17be15d67a2f7149 (opens in a new tab)
- https://git.kernel.org/stable/c/47e15a8d12e366d0d261bcbc394394f44418938d (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-2026-76385 (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-2026-89479)Record last updated .