CVE-2026-99084: Linux kernel · readdir: take no inode lock on an immutable directory
Affects Linux kernelSource CVE Database V5
Not known to be exploited : upgrade to e08f57a7dcb83818c058e415988c23beb6c5a47f or 6d30b399ae28e5166d62484f81ccaefde6fe7996 when convenient.
Data as of 26 Oct 2026, 17:30 UTC
Rated Medium by Threat Radar's AI analysis · CVSS not yet scored by NVD
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 3% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in e08f57a7dcb83818c058e415988c23beb6c5a47f, 6d30b399ae28e5166d62484f81ccaefde6fe7996
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.
What to do
Upgrade Linux kernel to e08f57a7dcb83818c058e415988c23beb6c5a47f or 6d30b399ae28e5166d62484f81ccaefde6fe7996.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in– |
AI-suggested
A fix is available and has been applied in the Linux kernel versions identified by commits e08f57a7dcb83818c058e415988c23beb6c5a47f and 6d30b399ae28e5166d62484f81ccaefde6fe7996. Users should update their Linux kernel to a version including these fixes to resolve the issue.
Description
CVE-2026-99084 is a vulnerability in the Linux kernel's readdir implementation where an inode lock is unnecessarily taken on an immutable directory. This causes contention and stalls in certain mount namespace scenarios, particularly affecting nullfs directories shared across users. The issue is resolved by adding a flag to skip the lock for directories that never change or are never removed.