CVE-2026-46040
What it is
In the Linux kernel, the following vulnerability has been resolved: inotify: fix watch count leak when fsnotify_add_inode_mark_locked() fails When fsnotify_add_inode_mark_locked() fails in inotify_new_watch(), the error path calls inotify_remove_from_idr() but does not call dec_inotify_watches() to undo the preceding inc_inotify_watches(). This leaks a watch count, and repeated failures can exhaust the max_user_watches limit with -ENOSPC even when no watches are active. Prior to commit 1cce1eea0aff ("inotify: Convert to using per-namespace limits"), the watch count was incremented after fsnotify_add_mark_locked() succeeded, so this path was not affected. The conversion moved inc_inotify_watches() before the mark insertion without adding the corresponding rollback. Add the missing dec_inotify_watches() call in the error path.
At a glance
- Exploitability
- Can be exploited locally on the machine with a low-privilege account. High risk of service disruption.
- Exploit odds
- 0.1% chance of exploitation in the next 30 days (EPSS).
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 0.1% in the next 30 days (EPSS).
- Severity: 5.5 MEDIUM (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 0.1% · EPSS, next 30 days
- Record status
- Modified
Affected
- Linux Kernel < 5.10.258
- Linux Kernel < 5.15.209
- Linux Kernel < 6.1.175
- Linux Kernel < 6.6.140
- Linux Kernel < 6.12.86
- Linux Kernel < 6.18.27
- Linux Kernel < 7.0.4
Attack profile CVSS 3.1 · 5.5
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Raw vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2026-46040.md and follow it. Check whether this project is affected by CVE-2026-46040. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
Fix and advisories
- https://git.kernel.org/stable/c/10edf7e0ffdc7faa18e2244b17722c1b882b8273
- https://git.kernel.org/stable/c/3ab58cf42c46bf2366d2f55ae5c59299d5e178b7
- https://git.kernel.org/stable/c/3ad9ccea1b25435f6179b57aa891960beb7ce8f9
- https://git.kernel.org/stable/c/6a320935fa4293e9e599ec9f85dc9eb3be7029f8
- https://git.kernel.org/stable/c/73ddc8518a32baff6bc17afda4ee1ebae5b4ed12
- https://git.kernel.org/stable/c/8bcc1cd237ab5ccfdd102869fa031c541943cf40
- https://git.kernel.org/stable/c/9e48844f708eb48bae4e79cb21edc097c966306d
- https://git.kernel.org/stable/c/fdaa42ca370d056428e5e171247c8fdce8dff36a
References
- https://git.kernel.org/stable/c/10edf7e0ffdc7faa18e2244b17722c1b882b8273
- https://git.kernel.org/stable/c/3ab58cf42c46bf2366d2f55ae5c59299d5e178b7
- https://git.kernel.org/stable/c/3ad9ccea1b25435f6179b57aa891960beb7ce8f9
- https://git.kernel.org/stable/c/6a320935fa4293e9e599ec9f85dc9eb3be7029f8
- https://git.kernel.org/stable/c/73ddc8518a32baff6bc17afda4ee1ebae5b4ed12
- https://git.kernel.org/stable/c/8bcc1cd237ab5ccfdd102869fa031c541943cf40
- https://git.kernel.org/stable/c/9e48844f708eb48bae4e79cb21edc097c966306d
- https://git.kernel.org/stable/c/fdaa42ca370d056428e5e171247c8fdce8dff36a
- https://cert-portal.siemens.com/productcert/html/ssa-019113.html
- https://cert-portal.siemens.com/productcert/html/ssa-457936.html
- https://cert-portal.siemens.com/productcert/html/ssa-784472.html