VulnerabilityPublished 1 May 2026Updated 21 Oct 2026

CVE-2026-43053: Linux kernel · xfs: close crash window in attr dabtree inactivation

Affects Linux kernelSource CVE Database V5

Not known to be exploited · fixed in e5a3e3cdd9b3015ae79456c81beebfdbb5246c0f : patch Linux kernel soon.

Data as of 26 Oct 2026, 21:03 UTC

Severity

High

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

EPSS: 0.1% chance of exploitation in 30 days – higher than 1% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in e5a3e3cdd9b3015ae79456c81beebfdbb5246c0f, b854e1c4eff3473b6d3a9ae74129ac5c48bc0b61, 190d54d1d42878fce8c735c2d9ac835725694d3a +1

Exploitation evidence

Disclosed: evidence found.
CVE published 1 May 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 Linux kernel to e5a3e3cdd9b3015ae79456c81beebfdbb5246c0f, b854e1c4eff3473b6d3a9ae74129ac5c48bc0b61, 190d54d1d42878fce8c735c2d9ac835725694d3a or 7ea3850b9ce005e70f502b308edb2d99ca074ed3.

Affected software

Product	Affected	Fixed in
LinuxLinux	Affected ≥ 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2, < e5a3e3cdd9b3015ae79456c81beebfdbb5246c0f	Fixed in e5a3e3cdd9b3015ae79456c81beebfdbb5246c0f
LinuxLinux	Affected ≥ 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2, < b854e1c4eff3473b6d3a9ae74129ac5c48bc0b61	Fixed in b854e1c4eff3473b6d3a9ae74129ac5c48bc0b61
LinuxLinux	Affected ≥ 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2, < 190d54d1d42878fce8c735c2d9ac835725694d3a	Fixed in 190d54d1d42878fce8c735c2d9ac835725694d3a
LinuxLinux	Affected ≥ 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2, < 7ea3850b9ce005e70f502b308edb2d99ca074ed3	Fixed in 7ea3850b9ce005e70f502b308edb2d99ca074ed3
LinuxLinux	Affected =2.6.12	Fixed in–

AI-suggested

A fix is available and has been applied in the Linux kernel. The patch ensures immediate removal of references to cancelled child blocks during inode attribute inactivation and enforces atomic truncation of attribute forks to prevent stale metadata pointers. Users should update to the fixed kernel versions identified by the commits e5a3e3cdd9b3015ae79456c81beebfdbb5246c0f, b854e1c4eff3473b6d3a9ae74129ac5c48bc0b61, 190d54d1d42878fce8c735c2d9ac835725694d3a, and 7ea3850b9ce005e70f502b308edb2d99ca074ed3. No additional mitigation is indicated.

Description

CVE-2026-43053 is a vulnerability in the Linux kernel's XFS filesystem related to the inactivation of inodes with node-format extended attributes. The flaw allows a crash window during attribute dabtree inactivation where stale pointers to cancelled blocks may remain, leading to metadata verification failures and potential filesystem corruption upon recovery. The issue arises if a log shutdown occurs between cancelling child leaf/node blocks and truncating the attribute bmap, causing recovery to encounter unreplayed or stale metadata blocks. The vulnerability has been fixed by ensuring immediate removal of references to cancelled child blocks and splitting attribute fork truncation into atomic phases to maintain crash safety.

Impact

This vulnerability can cause metadata corruption detection and filesystem unmounts requiring repair (xfs_repair) due to stale pointers to cancelled attribute blocks during recovery. It affects filesystem stability and availability by triggering metadata verification failures on mount after an unclean shutdown. There is no indication of remote code execution or privilege escalation, but the impact is denial of service through filesystem corruption and forced repair.

Summary

In the Linux kernel XFS filesystem, when inactivating an inode with node-format extended attributes, the function xfs_attr3_node_inactive() invalidates child leaf/node blocks but does not remove their references from parent nodes immediately. This relies on a subsequent truncation of the attribute fork to zero extents to prevent recovery from following stale pointers. However, if a log shutdown occurs after cancelling child blocks but before truncating the attribute bmap, recovery may suppress replay of cancelled blocks but still replay the attribute bmap, leaving stale pointers. On the next mount, this causes metadata verification failures and forces unmount and repair. The fix involves removing child block references immediately within the same transaction and splitting attribute fork truncation into two atomic phases to ensure crash safety and prevent stale metadata pointers.

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 26 Oct 2026, 21:03 UTC

Technical details

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