CVE-2026-74688

unknown

Assigned by CNA: linux

Published 2026-08-22 · Modified 2026-08-22

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CVSS v3

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CVSS v4 NEW

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not yet in upstream

VIR risk

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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.

Predictions

Exploit likelihood

20%

Patch ETA

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Heuristic predictions, AS-IS, for prioritization only.

Mitigations

No mitigations published for this CVE yet.

The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.

Propose a mitigation on Community Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here with source_tier=community-verified.

References

Community-verified mitigations for this CVE will appear above when contributors publish them.

Verify integrity in audit chain (admin only). AS-IS.