9.8

CVE-2026-74688: linux

CVSS: 9.8v3.1CriticalReceived
AliasesUBUNTU-CVE-2026-74688DEBIAN-CVE-2026-74688
Published 22-08-2026Last modified 16-10-2026
Open JSON

Vulnerability summary

CVE-2026-74688 is a critical (CVSS 9.8) vulnerability in linux. EPSS estimates a 0.50% chance of exploitation in the next 30 days, higher than 41.8% of scored vulnerabilities.

Overall risk
70/100
0100
High · default modelHow is this calculated?
CVSS score
9.8/10
010
Critical · v3.1 (CVE.org)
EPSS score
0.50%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 20 · Related 19
MGASA-2026-0506OPENSUSE-SU-2026:22091-1SUSE-SU-2026:24179-1SUSE-SU-2026:24181-1SUSE-SU-2026:24182-1SUSE-SU-2026:24184-1

Timeline

  1. 22-08-2026
    PublishedVulnerability first disclosed.
  2. 16-10-2026
    Last modifiedVulnerability information updated.

Description

In the Linux kernel, the following vulnerability has been resolved: sctp: clear control chunk transport if it is being removed sctp_make_heartbeat_ack() caches the destination transport in chunk->transport without taking a reference. When src_out_of_asoc_ok is enabled, the HEARTBEAT ACK may remain queued on control_chunk_list instead of being transmitted immediately. If the peer transport is removed while the chunk is still queued, sctp_assoc_rm_peer() drops the transport and schedules it for RCU freeing, but only clears cached transport pointers in out_chunk_list. The queued control chunk therefore retains a dangling transport pointer. Once an ASCONF_ACK clears the suppression and the queued control chunk is transmitted, SCTP dereferences the stale transport pointer, leading to a use-after-free. Fix this by also clearing chunk->transport for queued control chunks in control_chunk_list when removing the transport.

CVSS metrics

4 scores · 4 sources · 1 version

EPSS trend

Probability

0.50%

Chance of exploitation in the next 30 days

Percentile

42%

Versus all other CVEs

30-day change

0.00 pp

From 0.50% on 21-09-2026

21-09-202621-10-2026
EPSS score
0.50%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

No weakness data has been published for this record.

Affected systems

Ubuntu169 products
  • linuxAll versions (No fix recorded) | < 5.15.0-198.208
  • linux-allwinner-5.19All versions (No fix recorded)
  • linux-awsAll versions (No fix recorded) | < 5.15.0-1117.124
  • linux-aws-5.0All versions (No fix recorded)
  • linux-aws-5.11All versions (No fix recorded)
Debian2 products
  • linux< 6.1.187-1 | < 6.12.105-1 | < 7.1.9-1
  • linux-6.12< 6.12.107-1~deb12u1
Linux1 product
  • linux≥ 8a07eb0a50aebc8c95478d49c28c7f8419a26cef, < dbb3f418a8665ffb0514e1a9520ab6a1c5d4d886 | ≥ 8a07eb0a50aebc8c95478d49c28c7f8419a26cef, < fad4766a74220fe579c6fcaa10ba01c23529814f | ≥ 8a07eb0a50aebc8c95478d49c28c7f8419a26cef, < 936658ec41c28c397ef390140e02d4c91ade92f0 | ≥ 8a07eb0a50aebc8c95478d49c28c7f8419a26cef, < 8de65194a04d2552cd39b6c67d942d490f22d174 | ≥ 8a07eb0a50aebc8c95478d49c28c7f8419a26cef, < 6160e756db81d6cb63e3e2952efcf6c5134be385 | ≥ 8a07eb0a50aebc8c95478d49c28c7f8419a26cef, < 18d704bdd809377dfd81a3c2f42426763b5da227 | ≥ 8a07eb0a50aebc8c95478d49c28c7f8419a26cef, < 4d6b9cac6df5e0cfef1a66b3edd7aebdb9e4b7e7 | ≥ 8a07eb0a50aebc8c95478d49c28c7f8419a26cef, < c9158ceaf27780ef64534ad72f44ffde3f8ccc49 | 3.1

3 vendors · 172 products

References

18 links
Show all 18 references