VulnerabilityPublished 23 Oct 2026

CVE-2026-99086: Linux kernel · dm-integrity: validate the superblock on resume

Source GCVE Database

Authoritative record:CVE-2026-99086· High

Not known to be exploited · fixed in fc79aeb86a2c244c1f1894e2d8f2966fe2b60fa2 : patch Linux kernel soon.

Data as of 26 Oct 2026, 14:05 UTC

Severity

High

Rated by Threat Radar · CVSS not yet scored by NVD

EPSS: 0.1% chance of exploitation in 30 days – higher than 5% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in fc79aeb86a2c244c1f1894e2d8f2966fe2b60fa2, e9ec5cbbaf4dd3a02ae3d81719f4fcb9b609aa8e, 454b67fcc28c18502e47dfb9f067b04c28628ada +5

Exploitation evidence

Disclosed: evidence found.
CVE published 23 Oct 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.

ghsa-ppgf-6cf3-2qjr

What to do

Upgrade to a fixed release listed under Affected software.

Affected software

Product	Affected	Fixed in
LinuxLinux	Affected >=6.18.16 <6.18.58 >=6.1.165 <6.2 >=6.6.128 <6.7 >=6.12.75 <6.13 >=6.19.6 <6.20	Fixed in fc79aeb86a2c244c1f1894e2d8f2966fe2b60fa2 e9ec5cbbaf4dd3a02ae3d81719f4fcb9b609aa8e 454b67fcc28c18502e47dfb9f067b04c28628ada 6.20 6.18.58 6.13 6.7 6.2
LinuxLinux	Affected =7.0	Fixed in–

AI-suggested

A fix has been implemented that snapshots the validated superblock during construction and prevents resuming if critical superblock fields have changed. Users should apply the official Linux kernel updates that include this fix. Since this is not a cloud service, remediation depends on applying kernel patches from the vendor or distribution.

Description

A vulnerability in the Linux kernel's dm-integrity module was resolved involving improper validation of the superblock on resume. The dm_integrity_resume() function re-reads the superblock without validating it, allowing discrepancies if the superblock is modified while the device is suspended. This can lead to out-of-bounds memory writes during journal access. The fix involves snapshotting the validated superblock during construction and refusing to resume if critical fields have changed.

Impact

This vulnerability can lead to kernel memory corruption due to out-of-bounds writes when resuming a dm-integrity device with a modified superblock. Such corruption could potentially cause system instability or crashes. No known exploits in the wild have been reported.

Summary

The dm-integrity module in the Linux kernel re-reads the superblock on resume via dm_integrity_resume() but does not validate the superblock contents against the originally validated version. Since the user can modify the superblock on the underlying device while the dm-integrity device is suspended, this can cause inconsistencies. Specifically, if the log2_sectors_per_block field increases, the journal entry index calculation can exceed the journal's bounds, causing a 512-byte write through lowmem_page_address(NULL), effectively a kernel memory corruption. The resolution is to snapshot the validated superblock during the constructor and refuse to resume if any on-disk geometry fields have changed.

References

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