VulnerabilityPublished 11 Sep 2026Updated 21 Oct 2026

CVE-2026-89566: Linux kernel · jbd2: check need_resched() when skipping busy checkpoint buffers

Affects Linux kernelSource CVE Database V5

Not known to be exploited · fixed in f9182a85991a0ad5cd2940df6db75f40ad90028c : update Linux kernel when convenient.

Data as of 26 Oct 2026, 13:47 UTC

Severity

Unrated

Rated by Threat Radar · CVSS not yet scored by NVD

EPSS: 0.2% chance of exploitation in 30 days – higher than 10% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in f9182a85991a0ad5cd2940df6db75f40ad90028c, f213e12ff5c9590b1034ae8da0e6d09665c772d0, f83c23286e54180cdc83a36463a60003534cc290 +5

Exploitation evidence

Disclosed: evidence found.
CVE published 11 Sep 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Upgrade to a fixed release listed under Affected software.

Affected software

Product	Affected	Fixed in
LinuxLinux	Affected >=5.15.129 <5.16 >=6.1.50 <6.2 >=6.4.13 <6.5	Fixed in f9182a85991a0ad5cd2940df6db75f40ad90028c f213e12ff5c9590b1034ae8da0e6d09665c772d0 f83c23286e54180cdc83a36463a60003534cc290 dc7ece0b827fe3b748db685fb85cd2fc3710c3f9 595cac7f1b32d009b97f83dd2b2d6a1a445e9bb4 6.5 6.2 5.16
LinuxLinux	Affected =6.5	Fixed in–

Description

In the Linux kernel, the following vulnerability has been resolved: jbd2: check need_resched() when skipping busy checkpoint buffers journal_shrink_one_cp_list() skips busy checkpoint buffers when called with JBD2_SHRINK_BUSY_SKIP. The continue statement on this path also skips the need_resched() check at the end of the loop body. Consequently, when a checkpoint list contains mostly busy buffers, the shrinker can walk the entire list while holding journal->j_list_lock, even when a reschedule has been requested. Large checkpoint lists under memory pressure can therefore cause long lock hold times and leave other CPUs spinning on j_list_lock, resulting in soft lockups or RCU stalls. Route the busy-buffer path through the need_resched() check so that the shrinker can release j_list_lock and reschedule promptly, restoring parity with the clean-buffer path, which already checks need_resched(). This does not change which checkpoint buffers are eligible for removal.

References

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