CVE-2026-80980
A race condition in the Linux kernel’s SMC (Socket Message Control) subsystem allows an attacker to corrupt internal state by writing to three single‑bit flags that share a byte. The flaw was fixed by allocating each flag a separate byte, preventing accidental overlap. The issue is now resolved in the kernel source.
An official fix is available, so this entry is kept for 30 days and then removed automatically.
Who is affected
All Linux systems that use a kernel version before the patch, regardless of distribution. System administrators and users of servers or embedded devices running affected kernels are impacted.
Real-world impact
An attacker could trigger a kernel crash or corrupt memory, potentially leading to denial of service or privilege escalation on the affected system.
Why this severity
The CVSS score of 9.8 reflects that the vulnerability can be exploited remotely without authentication, with no user interaction required, and it allows complete compromise of confidentiality, integrity, and availability.
What to do about it
- 01Upgrade the Linux kernel to a version that includes the smc_connection flag fix.
NVD-referenced vendor advisory
Timeline
- Sep 11, 2026 · 2d agoPublishedDisclosed and added to the National Vulnerability Database.
- Sep 13, 2026 · 4h agoOfficial fix availableA vendor patch or mitigation now exists — see the remediation steps above.