VulnerabilityPublished 10 Aug 2026Updated 6 Nov 2026

CVE-2026-68132: Linux kernel · super: fix emergency thaw deadlock on frozen block devices

Affects Linux kernelSource CVE Database V5

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Not known to be exploited · fixed in c202aa03388fd1889b7aa4f7d677c49e22cd9700 : patch Linux kernel soon.

Data as of 6 Nov 2026, 18:18 UTC

Severity

High

Rated High by Threat Radar's AI analysis · No CVSS score from NVD or the CNA

Thin evidence

One scorer or none

Exploitation: No evidence of active exploitation and no public proof of concept
Automatable: Attackers cannot reliably automate steps 1–4 of the kill chain
Technical impact: Limited control over the software or limited information exposure

CISA SSVC assessment, 2026-11-06.

Patch

Available – fixed in c202aa03388fd1889b7aa4f7d677c49e22cd9700, 99719b5da9320ed344daee87d9c73d321a98f252, 96248aeddde794227a49af1a332a1e21b3c15d56 +5

Exploitation evidence

Disclosed: evidence found.
CVE published 10 Aug 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: 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 6 Nov 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.
Weaponized: A Metasploit exploit module or Exploit-DB entry exists (Metasploit scanner modules do not count), 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 ≥ 08fdc8a0138afaf324296a342f32ad26ec465e43, < c202aa03388fd1889b7aa4f7d677c49e22cd9700	Fixed in c202aa03388fd1889b7aa4f7d677c49e22cd9700
LinuxLinux	Affected ≥ 08fdc8a0138afaf324296a342f32ad26ec465e43, < 99719b5da9320ed344daee87d9c73d321a98f252	Fixed in 99719b5da9320ed344daee87d9c73d321a98f252
LinuxLinux	Affected ≥ 08fdc8a0138afaf324296a342f32ad26ec465e43, < 96248aeddde794227a49af1a332a1e21b3c15d56	Fixed in 96248aeddde794227a49af1a332a1e21b3c15d56
LinuxLinux	Affected ≥ 08fdc8a0138afaf324296a342f32ad26ec465e43, < 05536cad35f27b520d4b6f0e57c8cc5bfb6b0502	Fixed in 05536cad35f27b520d4b6f0e57c8cc5bfb6b0502
LinuxLinux	Affected ≥ 08fdc8a0138afaf324296a342f32ad26ec465e43, < 749d7aa0377aae32af8c0a4ad43371e7bf830ab5	Fixed in 749d7aa0377aae32af8c0a4ad43371e7bf830ab5
LinuxLinux	Affected ≥ 08fdc8a0138afaf324296a342f32ad26ec465e43, < 63d78b546eefc38ad9898dc839bfc94811ede547	Fixed in 63d78b546eefc38ad9898dc839bfc94811ede547

AI-suggested

A fix is available and has been applied in the Linux kernel. Users should update to the fixed kernel versions identified by the commits listed in the established facts to resolve the deadlock issue. No additional mitigation is required once the patch is applied.

Description

CVE-2026-68132 is a deadlock vulnerability in the Linux kernel affecting frozen block devices. The issue occurs when the emergency thaw worker attempts to thaw a frozen block device while holding certain locks, leading to a self-deadlock. This deadlock prevents subsequent unmount, freeze, or thaw operations on the affected filesystem and block device. The vulnerability has been fixed by changing the locking strategy to avoid holding the exclusive unmount lock during the thaw operation.

Impact

The deadlock prevents the emergency thaw worker from completing thaw operations on frozen block devices, effectively blocking any subsequent unmount, freeze, or thaw operations on the affected filesystem and block device. This can lead to system hangs or inability to manage block device states properly until the system is rebooted or patched.

Summary

The vulnerability in the Linux kernel involves a deadlock in the emergency thaw path for frozen block devices. Specifically, do_thaw_all_callback() holds the superblock unmount lock exclusively while calling bdev_thaw(), which in turn reacquires the same lock via fs_bdev_thaw(), causing a deadlock. This deadlock blocks the emergency thaw worker from proceeding, thereby preventing further unmount, freeze, or thaw operations on the filesystem and block device. The fix removes holding the unmount lock around the bdev_thaw() loop and instead pins the superblock with an active reference, maintaining validity without the lock. This resolves the deadlock condition and restores normal operation.

References

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 6 Nov 2026, 18:18 UTC

Technical details

References

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