CVE-2026-98655
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.
Read full descriptionShow less
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.
CVSS
NVD hasn't assigned a CVSS score to this CVE (common since the April 2026 policy change).
Exploitation probability (EPSS)
- Probability of exploitation in the next 30 days
- 0.18 %
- Percentile among all scored CVEs
- 7
- Score date
- 10/20/2026
EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).
Affected technologies (1)
⚠ AI-inferred from the description — NVD hasn't analyzed this CVE yet, these aren't verified CPEs.
References
Show 4 references
Raw JSON (NVD)
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{
"id": "CVE-2026-98655",
"cveTags": [],
"metrics": {},
"affected": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"affectedData": [
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "e17d43b93e544f5016c0251d2074c15568d5d963",
"lessThan": "8473f44db9f710ea6f8cafb22f2e3ba6cb8ca9a7",
"versionType": "git"
},
{
"status": "affected",
"version": "e17d43b93e544f5016c0251d2074c15568d5d963",
"lessThan": "e506333d1b9f42f1e402acebf1283af3c44a3809",
"versionType": "git"
},
{
"status": "affected",
"version": "e17d43b93e544f5016c0251d2074c15568d5d963",
"lessThan": "677d0b51ac1a0db55d768c4c6399210b3de0795b",
"versionType": "git"
},
{
"status": "affected",
"version": "e17d43b93e544f5016c0251d2074c15568d5d963",
"lessThan": "357e8a77a501d96c9517f01f4a211eed5e9c9184",
"versionType": "git"
}
],
"programFiles": [
"kernel/events/core.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "5.9"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "5.9",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "6.12.113",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.56",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.2.10",
"versionType": "semver",
"lessThanOrEqual": "7.2.*"
},
{
"status": "unaffected",
"version": "7.3",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"kernel/events/core.c"
],
"defaultStatus": "affected"
}
]
}
],
"published": "2026-10-18T16:17:18.797",
"references": [
{
"url": "https://git.kernel.org/stable/c/357e8a77a501d96c9517f01f4a211eed5e9c9184",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/677d0b51ac1a0db55d768c4c6399210b3de0795b",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/8473f44db9f710ea6f8cafb22f2e3ba6cb8ca9a7",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/e506333d1b9f42f1e402acebf1283af3c44a3809",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}
],
"vulnStatus": "Received",
"descriptions": [
{
"lang": "en",
"value": "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."
}
],
"lastModified": "2026-10-19T10:19:29.890",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}