CVE-2026-31640 (GCVE-0-2026-31640)

Vulnerability from cvelistv5 – Published: 2026-04-24 14:44 – Updated: 2026-08-05 12:24
VLAI
Title
rxrpc: Fix use of wrong skb when comparing queued RESP challenge serial
Summary
In the Linux kernel, the following vulnerability has been resolved: rxrpc: Fix use of wrong skb when comparing queued RESP challenge serial In rxrpc_post_response(), the code should be comparing the challenge serial number from the cached response before deciding to switch to a newer response, but looks at the newer packet private data instead, rendering the comparison always false. Fix this by switching to look at the older packet. Fix further[1] to substitute the new packet in place of the old one if newer and also to release whichever we don't use.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 5800b1cf3fd8ccab752a101865be1e76dac33142 , < 9132b1a7bf83b4a8042fffbc99d075b727a16742 (git)
Affected: 5800b1cf3fd8ccab752a101865be1e76dac33142 , < 20386e7f8d97475b8d815873e246423317ec4260 (git)
Affected: 5800b1cf3fd8ccab752a101865be1e76dac33142 , < b33f5741bb187db8ff32e8f5b96def77cc94dfca (git)
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Linux Linux Affected: 6.16
Unaffected: 0 , < 6.16 (semver)
Unaffected: 6.18.23 , ≤ 6.18.* (semver)
Unaffected: 6.19.13 , ≤ 6.19.* (semver)
Unaffected: 7.0 , ≤ * (original_commit_for_fix)
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Show details on NVD website
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}



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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
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  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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