VulnerabilityPublished 11 Sep 2026Updated 21 Oct 2026

CVE-2026-89642: Linux kernel · cifs: call pagecache_isize_extended() in cifs_setsize() when extending

Affects Linux kernelSource CVE Database V5

Not known to be exploited · fixed in e1f692b6da3e632a25d0b3a99f833bb609bae1a3 : 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 e1f692b6da3e632a25d0b3a99f833bb609bae1a3, c510edb9734af1c274d18f4f31a471a166bbc7e8, 5463d96cd2e46064ceefcf861b028745a4f4c373 +2

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 ≥ 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2, < e1f692b6da3e632a25d0b3a99f833bb609bae1a3	Fixed in e1f692b6da3e632a25d0b3a99f833bb609bae1a3
LinuxLinux	Affected ≥ 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2, < c510edb9734af1c274d18f4f31a471a166bbc7e8	Fixed in c510edb9734af1c274d18f4f31a471a166bbc7e8
LinuxLinux	Affected ≥ 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2, < 5463d96cd2e46064ceefcf861b028745a4f4c373	Fixed in 5463d96cd2e46064ceefcf861b028745a4f4c373
LinuxLinux	Affected ≥ 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2, < 40c16040783abcc240bd1b453e679ea6ca30e19e	Fixed in 40c16040783abcc240bd1b453e679ea6ca30e19e
LinuxLinux	Affected ≥ 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2, < 12bafe32f09c0d24f5096154b59c347b9c6606e0	Fixed in 12bafe32f09c0d24f5096154b59c347b9c6606e0
LinuxLinux	Affected =2.6.12	Fixed in–

Description

In the Linux kernel, the following vulnerability has been resolved: cifs: call pagecache_isize_extended() in cifs_setsize() when extending cifs_setsize() calls truncate_pagecache() but skips pagecache_isize_extended() on extension. truncate_setsize() shows the correct pattern: i_size_write(inode, newsize); if (newsize > oldsize) pagecache_isize_extended(inode, oldsize, newsize); truncate_pagecache(inode, newsize); pagecache_isize_extended() zeroes the tail of the page straddling old EOF. Without it, dirty bytes in that region can be written back to the server, exposing stale data in the newly extended range.

References

Community reviews

Loading reviews…