{"id":"CVE-2026-89543","title":"In the Linux kernel, the following vulnerability has been resolved:\n\nsunrpc: fix use-after-free in __rpc_clnt_handle_event and __rpc_clnt_remove_pipedir\n\nNormal client creation goes through rpc_setup_pipedir(), which records\nclnt->pipefs…","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nsunrpc: fix use-after-free in __rpc_clnt_handle_event and __rpc_clnt_remove_pipedir\n\nNormal client creation goes through rpc_setup_pipedir(), which records\nclnt->pipefs…","severity":"high","cvss":7,"cvssVector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H","cwe":["CWE-825"],"vendor":"Linux","product":"Linux","affected":["Linux >= bfca5fb4e97c46503ddfc582335917b0cc228264 < 59527bbfb1eabdb28e95e7c725886cc2c2899cb3","Linux >= bfca5fb4e97c46503ddfc582335917b0cc228264 < e769fcde3cc73e847b1eb3acd40c04a291cb0c0c","Linux >= bfca5fb4e97c46503ddfc582335917b0cc228264 < cdf7a233cb94774b0e7df42d9157077983f5022c","Linux >= bfca5fb4e97c46503ddfc582335917b0cc228264 < 932a8cf6abb2b2f8677b79153a823108d8861fe2","Linux 17866066b8ac1cc38fb449670bc15dc9fee4b40a","Linux 7d61d1da2ed1f682c41cae0c8d4719cdaccee5c5","Linux dedf2a0eb9448ae73b270743e6ea9b108189df46","Linux 194454afa6aa9d6ed74f0c57127bc8beb27c20df","Linux 7749fd2dbef72a52b5c9ffdbf877691950ed4680","Linux 1cdb52ffd6600a37bd355d8dce58ecd03e55e618","Linux cc2e7ebbeb1d0601f7f3c8d93b78fcc03a95e44a","Linux >= 4.19.318 < 4.20","Linux >= 5.4.280 < 5.5","Linux >= 5.10.202 < 5.11","Linux >= 5.15.140 < 5.16","Linux >= 6.1.64 < 6.2","Linux >= 6.5.13 < 6.6","Linux >= 6.6.3 < 6.7","Linux 6.7"],"published":"2026-09-11","updated":"2026-09-21","sourceUpdated":"2026-09-21T14:17:22.840","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-89543","references":[{"url":"https://git.kernel.org/stable/c/59527bbfb1eabdb28e95e7c725886cc2c2899cb3","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/932a8cf6abb2b2f8677b79153a823108d8861fe2","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/cdf7a233cb94774b0e7df42d9157077983f5022c","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/e769fcde3cc73e847b1eb3acd40c04a291cb0c0c","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89543.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-89543"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2532038"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-89543"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-89543"},{"url":"https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-89543.mbox"}],"tags":["nvd","cve.org","csaf","vex","red-hat"],"epss":0.002,"epssPercentile":0.10119,"cvssSource":"vendor","ingestedAt":"2026-09-14T11:11:19.886Z","slug":"CVE-2026-89543","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nsunrpc: fix use-after-free in __rpc_clnt_handle_event and __rpc_clnt_remove_pipedir\n\nNormal client creation goes through rpc_setup_pipedir(), which records\nclnt->pipefs_sb, but the mount-event path in __rpc_clnt_handle_event()\ncalls rpc_setup_pipedir_sb() directly and never refreshes that field.\nThe umount path also removes the directory without clearing\nclnt->pipefs_sb.\n\nAfter a late pipefs mount or any remount, rpc_clnt_remove_pipedir()\ncompares the current superblock against a stale pipefs_sb pointer and\nskips cleanup, leaving pipefs dentries whose inode private data still\npoints at a freed rpc_clnt, leading to a potential use-after-free during\nsubsequent rpc_info_open() or rpc_show_info() calls.\n\nFix this by properly updating clnt->pipefs_sb upon mount events and\nclearing it during unmount or failure paths.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.\n\n## Vendor advisories\n\n- **Red Hat VEX** · Moderate · affected: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 · no fix planned: Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9, … · updated 2026-09-14 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89543.json)","depth":"twilight","depthScore":39,"depthScoreParts":{"impact":38.5,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[{"seq":202752,"id":"CVE-2026-89543","ts":1789403715619,"field":"cvss","old":null,"new":"7"},{"seq":202751,"id":"CVE-2026-89543","ts":1789403715619,"field":"severity","old":"none","new":"high"},{"seq":109644,"id":"CVE-2026-89543","ts":1789183732767,"field":"cvss","old":null,"new":"4.1"},{"seq":109643,"id":"CVE-2026-89543","ts":1789183732767,"field":"severity","old":"none","new":"medium"}]}