CVE-2026-74688

CRITICALPre-NVD 9.89.8—
EchelonGraph scoreHIGH confidence

Score 9.8 from GitHub Security Advisory (severity: CRITICAL) published 2026-08-22. a secondary CVSS source baseline 9.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
Trending — 4 sources updated this week
9.8EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 1%CVSS: 9.8Exploit: None knownExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

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 v3
9.8
EG Score
9.8(high)
EG Risk
49(Track)
EG Risk 49/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity98% × 45%
Exploitation1% × 40%
Automatability30% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
1%
EPSS %ILE
41%
KEV
Not listed

Published

August 22, 2026

Last Modified

August 25, 2026

Advisory Details (8)

Auto-updated Aug 25, 2026
No patch confirmed yet.
generic

sctp: clear control chunk transport if it is being removed - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/fad4766a74220fe579c6fcaa10ba01c23529814f
generic

sctp: clear control chunk transport if it is being removed - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/dbb3f418a8665ffb0514e1a9520ab6a1c5d4d886
generic

sctp: clear control chunk transport if it is being removed - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/c9158ceaf27780ef64534ad72f44ffde3f8ccc49
generic

sctp: clear control chunk transport if it is being removed - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/936658ec41c28c397ef390140e02d4c91ade92f0
generic

sctp: clear control chunk transport if it is being removed - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/8de65194a04d2552cd39b6c67d942d490f22d174
generic

sctp: clear control chunk transport if it is being removed - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/6160e756db81d6cb63e3e2952efcf6c5134be385
generic

sctp: clear control chunk transport if it is being removed - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/4d6b9cac6df5e0cfef1a66b3edd7aebdb9e4b7e7
generic

sctp: clear control chunk transport if it is being removed - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/18d704bdd809377dfd81a3c2f42426763b5da227

Vendor Advisories for CVE-2026-74688(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Data Freshness Timeline

(refreshed 47× in last 7d / 50× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-08-30 03:11 UTCEG score recompute
  2. 2026-08-30 03:11 UTCGHSA enrichment
  3. 2026-08-30 01:22 UTCEPSS rescore
  4. 2026-08-29 23:27 UTCGHSA enrichment
  5. 2026-08-29 19:42 UTCGHSA enrichment
  6. 2026-08-29 15:58 UTCGHSA enrichment
  7. 2026-08-29 12:13 UTCGHSA enrichment
  8. 2026-08-29 08:17 UTCGHSA enrichment
  9. 2026-08-29 04:32 UTCGHSA enrichment
  10. 2026-08-29 00:43 UTCEG score recompute
  11. 2026-08-29 00:43 UTCGHSA enrichment
  12. 2026-08-28 21:42 UTCEPSS rescore
  13. 2026-08-28 17:34 UTCGHSA enrichment
  14. 2026-08-28 13:33 UTCGHSA enrichment
  15. 2026-08-28 09:46 UTCGHSA enrichment
  16. 2026-08-28 05:59 UTCGHSA enrichment
  17. 2026-08-28 02:15 UTCGHSA enrichment
  18. 2026-08-27 22:25 UTCGHSA enrichment
  19. 2026-08-27 18:42 UTCGHSA enrichment
  20. 2026-08-27 14:50 UTCEG score recompute
  21. 2026-08-27 14:50 UTCGHSA enrichment
  22. 2026-08-27 14:25 UTCEPSS rescore
  23. 2026-08-27 11:05 UTCGHSA enrichment
  24. 2026-08-27 07:22 UTCGHSA enrichment
  25. 2026-08-27 03:38 UTCGHSA enrichment
Show 25 more
  1. 2026-08-26 23:55 UTCGHSA enrichment
  2. 2026-08-26 20:11 UTCGHSA enrichment
  3. 2026-08-26 16:24 UTCEG score recompute
  4. 2026-08-26 16:24 UTCGHSA enrichment
  5. 2026-08-26 14:47 UTCEPSS rescore
  6. 2026-08-26 12:39 UTCGHSA enrichment
  7. 2026-08-26 08:53 UTCGHSA enrichment
  8. 2026-08-26 05:10 UTCGHSA enrichment
  9. 2026-08-26 01:24 UTCGHSA enrichment
  10. 2026-08-25 21:41 UTCGHSA enrichment
  11. 2026-08-25 17:39 UTCGHSA enrichment
  12. 2026-08-25 13:55 UTCEG score recompute
  13. 2026-08-25 13:55 UTCGHSA enrichment
  14. 2026-08-25 13:49 UTCEPSS rescore
  15. 2026-08-25 10:12 UTCEG score recompute
  16. 2026-08-25 10:12 UTCGHSA enrichment
  17. 2026-08-25 06:29 UTCEG score recompute
  18. 2026-08-25 06:29 UTCGHSA enrichment
  19. 2026-08-25 05:55 UTCEG score recompute▲ 9.80
  20. 2026-08-25 05:55 UTCGHSA enrichment
  21. 2026-08-25 05:55 UTCMITRE cvelistV5CVSS v3 → 9.8 · severity → CRITICAL
  22. 2026-08-24 14:18 UTCEPSS rescore
  23. 2026-08-22 16:24 UTCNVD update
  24. 2026-08-22 15:39 UTCEG score recompute
  25. 2026-08-22 15:35 UTCMITRE cvelistV5first tracked

Frequently asked(5)

What is CVE-2026-74688?
CVE-2026-74688 is a critical vulnerability published on August 22, 2026. In the Linux kernel, the following vulnerability has been resolved: sctp: clear control chunk transport if it is being removed sctpmakeheartbeat_ack() caches the destination transport in chunk->transport without taking a reference. When srcoutofasocok is enabled, the HEARTBEAT ACK may remain queued…
When was CVE-2026-74688 disclosed?
CVE-2026-74688 was first published in the National Vulnerability Database on August 22, 2026, with the most recent update on August 25, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-74688 actively exploited?
CVE-2026-74688 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 1% probability of exploitation in the next 30 days, which ranks it in the top 59.4% of all scored CVEs.
What is the CVSS score of CVE-2026-74688?
CVE-2026-74688 has a CVSS v3 base score of 9.8 (NVD).
How do I remediate CVE-2026-74688?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-74688, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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