# 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.

- **Severity:** Not scored
- **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:** Yes
- **Published:** 11 Sep 2026
- **Updated:** 19 Oct 2026
- **Also known as:** AZL-100424, BELL-CVE-2026-81013, DEBIAN-CVE-2026-81013, GHSA-66mm-3gmh-q6v8, UBUNTU-CVE-2026-81013

## 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.

## Is CVE-2026-81013 being exploited?

There is no known exploitation of CVE-2026-81013 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-81013 and fix it if it is affected.

What it is: 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.
Exploitation: There is no known exploitation of CVE-2026-81013 in the wild and no public exploit code.

Affected product: Linux. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-81013/ (Markdown: https://insights.sbomify.com/CVE-2026-81013/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-81013
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-81013
- OSV: https://osv.dev/vulnerability/CVE-2026-81013

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-81013/
Summaries are generated and may contain mistakes; the official description above is the record.