Skip to main content
VulnerabilityPublished Updated

CVE-2026-63971: Linux kernel · sctp: fix race between sctp_wait_for_connect and peeloff

Affects Linux kernelSource CVE Database V5

0

Not known to be exploited · CVSS 7.8 High · fixed in f14fe6395a8b3d961a61e138ad7b36ba3626dd4e : patch Linux kernel soon.

Data as of 26 Oct 2026, 17:16 UTC

CVSS 3.1 base score
7.8High
How severe the flaw is on the 0–10 CVSS scale.
EPSS
0.1% chance of exploitation in 30 days – higher than 2% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CISA SSVC
Exploitation
No evidence of active exploitation and no public proof of concept
Automatable
Attackers cannot reliably automate steps 1–4 of the kill chain
Technical impact
Total control over the software or total information disclosure

CISA SSVC assessment, 2026-10-16.

Patch
Available – fixed in f14fe6395a8b3d961a61e138ad7b36ba3626dd4e, bcfeac79af740735ace44008b4a11b8e5add20f5, 68667ee4c7dadf7f63167234e2a1af09b3f7874e +5
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Exploitation evidence

  1. Disclosed: evidence found.

    CVE published 19 Jul 2026

  2. Detectable: no evidence on record.

    No public nuclei template indexed

  3. Weaponised: no evidence on record.

    No public exploit code indexed in Metasploit or Exploit-DB

  4. Exploited in the wild: no evidence on record.

    Not in CISA KEV and no source reports exploitation

  5. Observed by OffSeq Mirage: no evidence on record.

    No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.

What to do

Upgrade to a fixed release listed under Affected software.

Affected software

ProductAffectedFixed in
LinuxLinuxAffected
  • ≥ 668c9beb9020d5834ee9e43c208190a07d2b1928, < f14fe6395a8b3d961a61e138ad7b36ba3626dd4e
Fixed in
  • f14fe6395a8b3d961a61e138ad7b36ba3626dd4e
LinuxLinuxAffected
  • ≥ 668c9beb9020d5834ee9e43c208190a07d2b1928, < bcfeac79af740735ace44008b4a11b8e5add20f5
Fixed in
  • bcfeac79af740735ace44008b4a11b8e5add20f5
LinuxLinuxAffected
  • ≥ 668c9beb9020d5834ee9e43c208190a07d2b1928, < 68667ee4c7dadf7f63167234e2a1af09b3f7874e
Fixed in
  • 68667ee4c7dadf7f63167234e2a1af09b3f7874e
LinuxLinuxAffected
  • ≥ 668c9beb9020d5834ee9e43c208190a07d2b1928, < 6140cfa721451fa6e18e134e709703c2bf34d0fb
Fixed in
  • 6140cfa721451fa6e18e134e709703c2bf34d0fb
LinuxLinuxAffected
  • ≥ 668c9beb9020d5834ee9e43c208190a07d2b1928, < 634a9af8a26a84d8b0d7b3b643204b344b42d9fb
Fixed in
  • 634a9af8a26a84d8b0d7b3b643204b344b42d9fb
LinuxLinuxAffected
  • ≥ 668c9beb9020d5834ee9e43c208190a07d2b1928, < 8e9b56051d24540cfbf39194618708c4a7633549
Fixed in
  • 8e9b56051d24540cfbf39194618708c4a7633549

Description

In the Linux kernel, the following vulnerability has been resolved: sctp: fix race between sctp_wait_for_connect and peeloff sctp_wait_for_connect() drops and re-acquires the socket lock while waiting for the association to reach ESTABLISHED state. During this window, another thread can peeloff the association to a new socket via getsockopt(SCTP_SOCKOPT_PEELOFF), changing asoc->base.sk. After re-acquiring the old socket lock, sctp_wait_for_connect() returns success without noticing the migration — the caller then accesses the association under the wrong lock in sctp_datamsg_from_user(). Add the same sk != asoc->base.sk check that sctp_wait_for_sndbuf() already has, returning an error if the association was migrated while we slept.

References

Community reviews

Loading reviews…