Linux kernel bug causes heap corruption and potential local privilege escalation across widely deployed Linux systems.
CVE-2026-89992
Kernel cpuidle frees wrong pointer, causing heap corruption.
do firstUpgrade to a fixed release: < 5.18, >= 6.1.188 and <= 6.1.*, >= 6.6.157 and <= 6.6.*, >= 6.12.110 and <= 6.12.* (+3 more below).
Is CVE-2026-89992 being exploited?
Not confirmed. CVE-2026-89992 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.18% probability of exploitation in the next 30 days.
How severe is CVE-2026-89992?
CVE-2026-89992 is rated High with a CVSS score of 8.4. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-89992?
Yes. A fix has been recorded for CVE-2026-89992. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-89992 affect?
CVE-2026-89992 affects Linux kernel (cpuidle/dt_idle). Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-89992?
Apply vendor/kernel updates and reboot; restrict untrusted local access.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Local attacker can trigger kernel heap corruption leading to crashes, local privilege escalation or arbitrary kernel code execution.
Patch when possible
- affected>= 9d976d6721dfb525b81ce981e1363c70c0975aab and < 1312ae33b91430ec99e69cd3d47f0e50a4ebf54b
- affected>= 9d976d6721dfb525b81ce981e1363c70c0975aab and < a38caa9ed0d5c61c17d88393b14b292199289c1f
- affected>= 9d976d6721dfb525b81ce981e1363c70c0975aab and < 09d002c8fb0261d35ce9d8a705de5db034ee90b8
- affected>= 9d976d6721dfb525b81ce981e1363c70c0975aab and < b519dfce1998c323e54a56f911cf708d9ba0e076
- affected>= 9d976d6721dfb525b81ce981e1363c70c0975aab and < 3394c7ba23336bdb7ece29127130fd01731d42d8
- affected>= 9d976d6721dfb525b81ce981e1363c70c0975aab and < 2b0ac85512b7f67479127b2713254490662eb13d
- affected5.18
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.
timeline
- 16 Sept 2026Published
- 18 Sept 2026Analysed by vulneraibility.com · 2 days later
- 19 Oct 2026CVE record last updated · 31 days later
- Linkgit.kernel.org /stable/c/1312ae33b91430ec99e69cd3d47f0e50a4ebf54b
- Linkgit.kernel.org /stable/c/a38caa9ed0d5c61c17d88393b14b292199289c1f
- Linkgit.kernel.org /stable/c/09d002c8fb0261d35ce9d8a705de5db034ee90b8
- Linkgit.kernel.org /stable/c/b519dfce1998c323e54a56f911cf708d9ba0e076
- Linkgit.kernel.org /stable/c/3394c7ba23336bdb7ece29127130fd01731d42d8
- Linkgit.kernel.org /stable/c/2b0ac85512b7f67479127b2713254490662eb13d
sources
- CVE List (CVE.org): description, affected versions, references; CVE Terms of Use
- NVD: CVSS and CPE data
- FIRST EPSS: exploit probability and percentile
- Summary, impact and triage tags: written by our AI analysis pipeline from the sources above. Check them against the sources.