SB20260216104 - Improper locking in Linux kernel isdn mISDN driver
Published: February 16, 2026
Security Bulletin ID
SB20260216104
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 security vulnerability.
1) Improper locking (CVE-ID: CVE-2026-23121)
The vulnerability allows a local user to perform a denial of service (DoS) attack.
The vulnerability exists due to improper locking within the mISDN_read(), mISDN_poll() and misdn_add_timer() functions in drivers/isdn/mISDN/timerdev.c. A local user can perform a denial of service (DoS) attack.
Remediation
Install update from vendor's website.
References
- https://git.kernel.org/stable/c/13f3b3b87068898056db4c79ee67052fbde11d43
- https://git.kernel.org/stable/c/7ac345a93af31358e18e9606eb7b354691bf6757
- https://git.kernel.org/stable/c/8175dbf174d487afab81e936a862a8d9b8a1ccb6
- https://git.kernel.org/stable/c/aa6e33cd74ca4965f2bbcb025e0b672fb0168a69
- https://git.kernel.org/stable/c/accc3f8266d2a49881dbcf78c459477f4efa0ff3
- https://git.kernel.org/stable/c/d5d99cb9e0839093cd53aa3b28176fce2f820ca0
- https://git.kernel.org/stable/c/fc8ba17fd3337bd8b1913c30b95df0fee00d8fb7