{"id":"AZL-109188","summary":"CVE-2026-98655 affecting package kernel 6.6.157.1-1","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":"2026-10-19T14:16:31.952809110Z","published":"2026-10-18T16:17:18Z","upstream":["CVE-2026-98655"],"references":[{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-98655"}],"affected":[{"package":{"name":"kernel","ecosystem":"Azure Linux:3","purl":"pkg:rpm/azure-linux/kernel"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"last_affected":"6.6.157.1-1"}]}],"database_specific":{"source":"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-109188.json"}}],"schema_version":"1.9.0"}