PT-2026-61086 · Linux · Linux Kernel

CVE-2026-53381 · Published 2026-07-19 · Updated 2026-07-21

Positive Technologies (AI Summary)

CVSS v3.1

7.8

High

Base vector

AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Name of the Vulnerable Software and Affected Versions Linux kernel (affected versions not specified)

Description A Use-After-Free (UAF) issue exists in the virtiofs component during submount umount operations. The problem occurs when iput() is called from fuse release end(), which can lead to a system crash (Oops) if the super block has already been destroyed. This happens because the wait counter is managed per connection rather than per superblock, failing to prevent the shutdown for all but the last submount instance. This flaw may allow local privilege escalation, code execution, and full system compromise.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.

Related Identifiers

CVE-2026-53381

Affected Products

Linux Kernel

References · 11

• https://nvd.nist.gov/vuln/detail/CVE-2026-53381 · Security Note
• https://git.kernel.org/stable/c/2181a09ba980f142650fb053666350ead4471cfe · Note
• https://twitter.com/DFIR_Lab/status/2079397290788127095 · Twitter Post
• https://git.kernel.org/stable/c/607a1d4c42f649e6197567c0448fd9ebb316cd42 · Note
• https://git.kernel.org/stable/c/1cc0e3a0c6499aaaa2f21a4fcbba388486afb25e · Note
• https://git.kernel.org/stable/c/39a2b95e008665c14f84e50ed411d898df7cd11b · Note
• https://git.kernel.org/stable/c/2abfd3ffbd9452f72535d96ff3982b3ab1f8f2f9 · Note
• https://git.kernel.org/stable/c/97c4691653d145dcc699eca5d3aba3219a520f1f · Note
• https://git.kernel.org/stable/c/06b41351779e9289e8785694ade9042ae85e41ea · Note
• https://git.kernel.org/stable/c/0b809199ff87c44487e516a725dd4be2185712ce · Note
• https://git.kernel.org/stable/c/e09412a714bcd49375198427bb4aa005037a9d6f · Note