VulnerabilityPublished 23 Oct 2026

CVE-2026-98921: Linux kernel · ovl: fix UAF in ovl_do_mkdir() debug print

Source GCVE Database

Authoritative record:CVE-2026-98921· Medium

Not known to be exploited : upgrade to ae146bc1abdeb4607abf2975b858c053024e8ac1 or 719bd33ab359c539a68a278c15a97deb77565cdb when convenient.

Data as of 26 Oct 2026, 14:05 UTC

Severity

Medium

Rated by Threat Radar · CVSS not yet scored by NVD

EPSS: 0.1% chance of exploitation in 30 days – higher than 4% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in ae146bc1abdeb4607abf2975b858c053024e8ac1, 719bd33ab359c539a68a278c15a97deb77565cdb

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-5m82-wc7w-682w

What to do

Upgrade Linux kernel to ae146bc1abdeb4607abf2975b858c053024e8ac1 or 719bd33ab359c539a68a278c15a97deb77565cdb.

Affected software

Product	Affected	Fixed in
LinuxLinux	Affected ≥ fe497f0759e0efb949f9480911d00b6045c21f50, < ae146bc1abdeb4607abf2975b858c053024e8ac1	Fixed in ae146bc1abdeb4607abf2975b858c053024e8ac1
LinuxLinux	Affected ≥ fe497f0759e0efb949f9480911d00b6045c21f50, < 719bd33ab359c539a68a278c15a97deb77565cdb	Fixed in 719bd33ab359c539a68a278c15a97deb77565cdb
LinuxLinux	Affected =6.19	Fixed in–

AI-suggested

A fix has been implemented to prevent the use-after-free by adjusting the debug print order in ovl_do_mkdir(). Users should apply the official kernel patch that corrects this behavior. Since this affects debug code enabled by CONFIG_OVERLAY_FS_DEBUG, disabling this debug option can mitigate exposure until the patch is applied.

Description

A use-after-free (UAF) vulnerability in the Linux kernel's overlay filesystem (ovl) was fixed in the ovl_do_mkdir() function. The issue occurs because ovl_do_mkdir() prints the input dentry after calling vfs_mkdir(), which may free or replace the dentry, leading to a UAF when CONFIG_OVERLAY_FS_DEBUG is enabled. The fix involves printing the dentry before the call and only printing the result afterward.

References

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