{"id":"CVE-2026-31630","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-31630","generatedAt":"2026-10-28T04:46:45.183Z","title":"In the Linux kernel, the following vulnerability has been resolved: rxrpc: proc: size address buffers for %pISpc output The AF_RXRPC procfs helpers format local and remote socket addresses into fixed 50-byte stack buffers with \"%pISpc\".","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nrxrpc: proc: size address buffers for %pISpc output\n\nThe AF_RXRPC procfs helpers format local and remote socket addresses into\nfixed 50-byte stack buffers with \"%pISpc\".\n\nThat is too small for the longest current-tree IPv6-with-port form the\nformatter can produce. In lib/vsprintf.c, the compressed IPv6 path uses a\ndotted-quad tail not only for v4mapped addresses, but also for ISATAP\naddresses via ipv6_addr_is_isatap().\n\nAs a result, a case such as\n\n  [ffff:ffff:ffff:ffff:0:5efe:255.255.255.255]:65535\n\nis possible with the current formatter. That is 50 visible characters, so\n51 bytes including the trailing NUL, which does not fit in the existing\nchar[50] buffers used by net/rxrpc/proc.c.\n\nSize the buffers from the formatter's maximum textual form and switch the\ncall sites to scnprintf().\n\nChanges since v1:\n- correct the changelog to cite the actual maximum current-tree case\n  explicitly\n- frame the proof around the ISATAP formatting path instead of the earlier\n  mapped-v4 example","published":"2026-04-24T15:16:42.000Z","lastModified":"2026-10-21T13:18:41.000Z","status":"Modified","sourceIdentifier":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","cvss":{"version":"3.1","score":7.8,"severity":"HIGH","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"},"cwe":["CWE-121"],"affected":["linux/linux kernel"],"epss":{"score":0.00175,"percentile":0.06926,"date":"2026-10-27","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"high","text":"High impact if exploited, but EPSS currently rates exploitation as unlikely (0.18%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[],"references":[{"url":"https://git.kernel.org/stable/c/10ebed83f9f6414af4e85bc85ffaeda7effdd874","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/235b2115de892eab2e107a42efa7a4347baaa80b","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/386c86412608d3449006a318a662cbcd6ca1f668","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/625af53a1564e31bb2df9adc3739df46137f46c1","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/808a34cdbe8ce336c202d8ea6d5e48496764dc37","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/a44ce6aa2efb61fe44f2cfab72bb01544bbca272","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/a6042b8066b24dbcc7945616a157d4d43e463668","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/db297c78ce537c9ac96f0eda9b25ad72c8caefa9","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-784472.html","source":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-31630","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}