CVE-2026-81013 platform/x86: hp-bioscfg: fix heap OOB read on empty password write
A local attacker can trigger a heap out-of-bounds read in the HP BIOS configuration driver by writing an empty password, potentially leaking adjacent kernel memory.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-81013?
CVE-2026-81013 is a 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 heap OOB read on empty password write
validate_password_input() computes length = strlen(buf) and then checks buf[length - 1] to strip a trailing newline, without checking that length is nonzero first. Writing an empty string (a bare '\n') to current_password or new_password gives length == 0, and buf[length - 1] reads buf[-1], one byte before the heap allocation holding the copied input.
KASAN confirms this directly:
BUG: KASAN: slab-out-of-bounds in store_password_instance.constprop.0+0x223/0x2a0 [hp_bioscfg] Read of size 1 at addr ffff88811bd8da9f by task sh/13740 ... store_password_instance.constprop.0+0x223/0x2a0 [hp_bioscfg] current_password_store+0x14/0x20 [hp_bioscfg] ... The buggy address is located 23 bytes to the right of allocated 8-byte region [ffff88811bd8da80, ffff88811bd8da88)
Reproduced identically via new_password_store. Execution continues past the bad read (the garbage byte only affects whether "length" is decremented by one), so the write completes and returns success; this is a pure information read past the buffer, not a crash, but it is still an out-of-bounds access KASAN correctly flags.
Fix by only checking buf[length - 1] when length is nonzero.
Which versions are affected by CVE-2026-81013?
How do I fix CVE-2026-81013?
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-2026-81013 being exploited?
There is no known exploitation of CVE-2026-81013 in the wild and no public exploit code.
Sources
Also known as AZL-100424, BELL-CVE-2026-81013, DEBIAN-CVE-2026-81013, GHSA-66mm-3gmh-q6v8, UBUNTU-CVE-2026-81013.