PT-2026-39039 · Linux · Linux Kernel

Published 2026-05-08 · Updated 2026-05-21 · CVE-2026-43378

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 A use-after-free issue exists in the SMB server component. The opinfo pointer, obtained through the rcu dereference(fp->f opinfo) function, is dereferenced after the rcu read unlock() function is called, creating a window for memory corruption.

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-2026-43378

Affected Products

Linux Kernel

References · 18

• https://osv.dev/vulnerability/BELL-CVE-2026-43378 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-43378 · Security Note
• https://ubuntu.com/security/CVE-2026-43378 · Vendor Advisory
• https://git.kernel.org/stable/c/e1b21e6066615e7d3d3a7aa2677e415e563fd7cc · Patch
• https://osv.dev/vulnerability/UBUNTU-CVE-2026-43378 · Vendor Advisory
• https://cve.org/CVERecord?id=CVE-2026-43378 · Security Note
• https://git.kernel.org/stable/c/8f5b1a7cb009a93c48e9e334a2f59a660f9afc07 · Patch
• https://git.kernel.org/stable/c/54b48ae83de8bb06e65079d96368efe359d4909c · Patch
• https://git.kernel.org/stable/c/b720c84087cb547f23ce03eab93568c1769e4556 · Patch
• https://security-tracker.debian.org/tracker/CVE-2026-43378 · Vendor Advisory
• https://git.kernel.org/stable/c/1e689a56173827669a35da7cb2a3c78ed5c53680 · Patch
• https://git.kernel.org/stable/c/190e5f808e8058640b408ccfed25440b441a718a · Patch
• https://osv.dev/vulnerability/DEBIAN-CVE-2026-43378 · Vendor Advisory
• https://git.kernel.org/linus/1e689a56173827669a35da7cb2a3c78ed5c53680 · Note
• https://t.me/cveNotify/164103 · Telegram Post