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.
Use CWE-401, Linux vendor hub and Linux Kernel product page to widen CVE-2026-31640 into its surrounding weakness, vendor, and product context.
Compare it with CVE-2026-7363, CVE-2026-7361 and CVE-2026-7359 for nearby disclosures in the same product family.