{"id":"CVE-2026-98655","summary":"perf: Require kernel access for text poke events","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nperf: Require kernel access for text poke events\n\nPerf events with exclude_kernel=1 can be opened without kernel perf\naccess. However, exclude_kernel does not suppress text-poke sideband\nrecords. Every PERF_RECORD_TEXT_POKE is marked PERF_RECORD_MISC_KERNEL\nand contains a raw kernel instruction address.\n\nAn unprivileged task can therefore open and mmap a task-local software\nevent with text_poke=1. Both opening a count-only tracepoint event and\nconfiguring UDP GRO for ESP-in-UDP cause updates to inline static calls;\nthe observer receives the relocated addresses of the modified instructions.\nFor a known kernel image, any such address reveals the runtime kernel\ntext base despite KASLR.\n\nCall perf_allow_kernel() whenever attr.text_poke is set, regardless of\nexclude_kernel. Events that neither monitor kernel execution nor request\ntext-poke records retain their existing permissions.","modified":"2026-10-19T02:47:02.927085127Z","published":"2026-10-18T15:44:05.722Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98655.json"},"references":[{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"},{"type":"WEB","url":"https://git.kernel.org/stable/c/357e8a77a501d96c9517f01f4a211eed5e9c9184"},{"type":"WEB","url":"https://git.kernel.org/stable/c/677d0b51ac1a0db55d768c4c6399210b3de0795b"},{"type":"WEB","url":"https://git.kernel.org/stable/c/8473f44db9f710ea6f8cafb22f2e3ba6cb8ca9a7"},{"type":"WEB","url":"https://git.kernel.org/stable/c/e506333d1b9f42f1e402acebf1283af3c44a3809"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98655.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-98655"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"e17d43b93e544f5016c0251d2074c15568d5d963"},{"fixed":"8473f44db9f710ea6f8cafb22f2e3ba6cb8ca9a7"},{"fixed":"e506333d1b9f42f1e402acebf1283af3c44a3809"},{"fixed":"677d0b51ac1a0db55d768c4c6399210b3de0795b"},{"fixed":"357e8a77a501d96c9517f01f4a211eed5e9c9184"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-98655.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"5.9.0"},{"fixed":"6.12.113"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.56"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.2.10"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-98655.json"}}],"schema_version":"1.9.0"}