CVE-2026-98655 (GCVE-0-2026-98655)

Vulnerability from cvelistv5 – Published: 2026-10-18 15:44 – Updated: 2026-10-30 12:38
VLAI
Title
perf: Require kernel access for text poke events
Summary
In the Linux kernel, the following vulnerability has been resolved: perf: Require kernel access for text poke events Perf events with exclude_kernel=1 can be opened without kernel perf access. However, exclude_kernel does not suppress text-poke sideband records. Every PERF_RECORD_TEXT_POKE is marked PERF_RECORD_MISC_KERNEL and contains a raw kernel instruction address. An unprivileged task can therefore open and mmap a task-local software event with text_poke=1. Both opening a count-only tracepoint event and configuring UDP GRO for ESP-in-UDP cause updates to inline static calls; the observer receives the relocated addresses of the modified instructions. For a known kernel image, any such address reveals the runtime kernel text base despite KASLR. Call perf_allow_kernel() whenever attr.text_poke is set, regardless of exclude_kernel. Events that neither monitor kernel execution nor request text-poke records retain their existing permissions.
Severity
No CVSS data available.
Assigner
Linux CNA under the mitre root
CNA scorecard D 53/100 over 6820 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: e17d43b93e544f5016c0251d2074c15568d5d963 , < 4d8fc6290d14aa9e4c3b620fe3e5dc8ba3bea7e3 (git)
Affected: e17d43b93e544f5016c0251d2074c15568d5d963 , < c30886396eb1c0e9fdc4296398dea0db0ab37610 (git)
Affected: e17d43b93e544f5016c0251d2074c15568d5d963 , < 0e26d44b7c64b045adebcf5d614140f811f09752 (git)
Affected: e17d43b93e544f5016c0251d2074c15568d5d963 , < 8c38cb055f6a9651198780e4e4d5283de4039f79 (git)
Affected: e17d43b93e544f5016c0251d2074c15568d5d963 , < 8473f44db9f710ea6f8cafb22f2e3ba6cb8ca9a7 (git)
Affected: e17d43b93e544f5016c0251d2074c15568d5d963 , < e506333d1b9f42f1e402acebf1283af3c44a3809 (git)
Affected: e17d43b93e544f5016c0251d2074c15568d5d963 , < 677d0b51ac1a0db55d768c4c6399210b3de0795b (git)
Affected: e17d43b93e544f5016c0251d2074c15568d5d963 , < 357e8a77a501d96c9517f01f4a211eed5e9c9184 (git)
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Linux Linux Affected: 5.9
Unaffected: 0 , < 5.9 (semver)
Unaffected: 5.10.273 , ≤ 5.10.* (semver)
Unaffected: 5.15.224 , ≤ 5.15.* (semver)
Unaffected: 6.1.191 , ≤ 6.1.* (semver)
Unaffected: 6.6.160 , ≤ 6.6.* (semver)
Unaffected: 6.12.113 , ≤ 6.12.* (semver)
Unaffected: 6.18.56 , ≤ 6.18.* (semver)
Unaffected: 7.2.10 , ≤ 7.2.* (semver)
Unaffected: 7.3 , ≤ * (original_commit_for_fix)
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    "dateUpdated": "2026-10-30T12:38:27.085Z",
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      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: perf: Require kernel access for text poke events",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98655.json",
      "version": "3"
    }
  }
}



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