PT-2026-34349 · Linux · Linux Kernel

Published 2026-04-22 · Updated 2026-05-07 · CVE-2026-31444

Positive Technologies (AI Summary)

CVSS v3.1

9.8

Critical

Base vector

AV:N/AC:L/PR:N/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 The smb grant oplock() function in ksmbd contains two issues. First, a use-after-free occurs when opinfo is linked into ci->m op list before add lease global list() is called; if the latter fails, the error path frees opinfo while it remains linked, leading concurrent readers to dereference the freed node. Second, a NULL dereference occurs because opinfo->o fp is assigned after add lease global list() publishes opinfo on the global lease list, allowing find same lease key() to dereference opinfo->o fp->f ci while o fp is still NULL.

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

Use After Free

Weakness Enumeration

CWE-416

Related Identifiers

CVE-2026-31444

Affected Products

Linux Kernel

References · 17

• https://git.kernel.org/stable/c/6d7e5a918c1d0aad06db0e17677b66fc9a471021 · Patch
• https://git.kernel.org/stable/c/7de55bba69cbf0f9280daaea385daf08bc076121 · Patch
• https://osv.dev/vulnerability/UBUNTU-CVE-2026-31444 · Vendor Advisory
• https://git.kernel.org/stable/c/9e785f004cbc56390479b77375726ea9b0d1a8a6 · Patch
• https://cve.org/CVERecord?id=CVE-2026-31444 · Security Note
• https://ubuntu.com/security/CVE-2026-31444 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-31444 · Security Note
• https://osv.dev/vulnerability/BELL-CVE-2026-31444 · Vendor Advisory
• https://osv.dev/vulnerability/DEBIAN-CVE-2026-31444 · Vendor Advisory
• https://security-tracker.debian.org/tracker/CVE-2026-31444 · Vendor Advisory
• https://git.kernel.org/stable/c/48623ec358c1c600fa1e38368746f933e0f1a617 · Patch
• https://git.kernel.org/stable/c/a5c6f6d6ceefed2d5210ee420fb75f8362461f46 · Patch
• https://docs.bell-sw.com/security/cves/CVE-2026-31444 · Note
• https://git.kernel.org/linus/48623ec358c1c600fa1e38368746f933e0f1a617 · Note
• https://twitter.com/CVEnew/status/2046980048234684818 · Twitter Post