# CVE-2026-110714: libsmb2 through 6.2 Heap Out-of-Bounds Read via decode_acl Integer Underflow

> A malicious SMB server can crash the libsmb2 client by sending crafted security descriptors that trigger an integer underflow and heap out-of-bounds read.

- **Severity:** High 7.1 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 14 Oct 2026
- **Updated:** 20 Oct 2026
- **Also known as:** DEBIAN-CVE-2026-110714, GHSA-f7hf-m5cf-j6wv, UBUNTU-CVE-2026-110714

## What is CVE-2026-110714?

CVE-2026-110714 is a high-severity vulnerability in sahlberg libsmb2, published on 14 Oct 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

### Official description

libsmb2 through 6.2 contains an integer underflow vulnerability in decode_acl that allows malicious SMB servers to trigger heap out-of-bounds reads via crafted security descriptors. Attackers controlling a server or intercepting unsigned sessions can send an AclSize below 8 in a QUERY_INFO reply, bypassing ACE bounds checks and crashing the client.

Weakness: CWE-191 (Integer Underflow (Wrap or Wraparound))

## Which versions are affected by CVE-2026-110714?


## How do I fix CVE-2026-110714?

No fix has been published for CVE-2026-110714 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-110714 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-110714 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-110714 and fix it if it is affected.

What it is: CVE-2026-110714 is a high-severity vulnerability in sahlberg libsmb2, published on 14 Oct 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-110714 exists.

Affected product: sahlberg libsmb2. 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-2026-110714/ (Markdown: https://insights.sbomify.com/CVE-2026-110714/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-110714
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-110714
- OSV: https://osv.dev/vulnerability/CVE-2026-110714

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-110714/
Summaries are generated and may contain mistakes; the official description above is the record.