CVE-2026-97503 genirq/proc: Size interrupt directory names for 10-digit interrupt numbers
A buffer overflow in the Linux kernel's proc filesystem allows local attackers to cause denial of service or execute code via large interrupt numbers.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-97503?
CVE-2026-97503 is a memory corruption vulnerability in Linux, published on 24 Sep 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
genirq/proc: Size interrupt directory names for 10-digit interrupt numbers
/proc/irq/<n>/ directory names are built in `char name[10]` buffers with `sprintf(name, "%u", irq)`.
Ten-digit IRQ numbers already need 11 bytes including the trailing NUL, and current sparse-IRQ configurations allow interrupt numbers in that range.
Size the temporary name buffer for the current decimal form and switch to bounded formatting when creating or removing the proc entry.
Which versions are affected by CVE-2026-97503?
How do I fix CVE-2026-97503?
Apply the vendor's patch.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2026-97503 being exploited?
There is no known exploitation of CVE-2026-97503 in the wild and no public exploit code.
Sources
Also known as AZL-103544, BELL-CVE-2026-97503, DEBIAN-CVE-2026-97503, GHSA-7j5w-cr4g-jjc9, UBUNTU-CVE-2026-97503.