SB2026052807 - Deadlock in Linux kernel x86 kernel
Published: May 28, 2026
Security Bulletin ID
SB2026052807
CSH Severity
Low
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Local access
Highest impact
Denial of service
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 vulnerability.
1) Deadlock (CVE-ID: CVE-2026-46063)
CWE-ID: CWE-833 - Deadlock
CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to improper locking in shadow stack signal frame handling during sigreturn when reading the shadow stack signal frame from userspace. A local user can trigger a page fault during sigreturn to cause a denial of service.
The issue can occur when a writer on another CPU is waiting on the mmap lock, leading to a deadlock in the fault handling path.
Remediation
Install update from vendor's website.
References
- https://git.kernel.org/stable/c/3d29db827502067626062f5c74dd502d14ab15bc
- https://git.kernel.org/stable/c/4f3374c990fb2adec06d20fd6d780927811c9aa0
- https://git.kernel.org/stable/c/9874b2917b9fbc30956fee209d3c4aa47201c64e
- https://git.kernel.org/stable/c/d042d69b417515959e49021fef008c9b04a99bd5
- https://git.kernel.org/stable/c/e2c2b044458cbf22da05264fa707308e8d4f86f9