CVE-2026-81012 platform/x86: hp-bioscfg: fix off-by-one write in hp_get_string_from_buffer()
An off-by-one error in the HP BIOS configuration driver allows writing a null byte past a buffer, potentially leading to memory corruption and privilege escalation.
- 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-2026-81012?
CVE-2026-81012 is a high-severity memory corruption vulnerability in Linux, published on 11 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:
platform/x86: hp-bioscfg: fix off-by-one write in hp_get_string_from_buffer()
hp_get_string_from_buffer() clamps the converted string length against the destination buffer size with "size > dst_size", so when the converted length is exactly equal to dst_size, conv_dst_size is left at dst_size and the unconditional NUL terminator write
dst[conv_dst_size] = 0;
lands one byte past the destination buffer. This is the same shape of bug as the previously fixed off-by-one in hp_convert_hexstr_to_str(): the buffer is sized correctly for the content, but the terminator write is never checked against that size.
Fix by changing the comparison to ">=" so conv_dst_size is always left with room for the terminator.
All fixed-size destinations that reach this function (path[512], current_value[512], current_password/current_value[64], and the per-entry buffers in encodings[][512] and prerequisites[][512]) are affected.
Which versions are affected by CVE-2026-81012?
How do I fix CVE-2026-81012?
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-2026-81012 being exploited?
There is no known exploitation of CVE-2026-81012 in the wild and no public exploit code.
Sources
Also known as AZL-100590, BELL-CVE-2026-81012, DEBIAN-CVE-2026-81012, GHSA-9p9c-f6r5-6rgq, UBUNTU-CVE-2026-81012.