# CVE-2026-119602: libmspack through 0.11alpha Uninitialized Memory Disclosure via MS-ZIP Decompressor Window


- **Severity:** Medium 6.3 (`CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Fix available:** No
- **Published:** 30 Oct 2026
- **Updated:** 30 Oct 2026
- **Also known as:** AZL-112667, AZL-112676, DEBIAN-CVE-2026-119602, ECHO-5b67-4d2c-9768, GHSA-xxh6-gw5r-86fm, UBUNTU-CVE-2026-119602

## What is CVE-2026-119602?

CVE-2026-119602 is a medium-severity vulnerability in kyz libmspack, published on 30 Oct 2026. 

### Official description

libmspack through 0.11alpha contains an uninitialized memory disclosure vulnerability in the MS-ZIP decompressor that allows attackers to leak heap data via unchecked back-reference distances. Attackers can supply a crafted MS-ZIP CAB file whose first block begins with a back-reference, causing cabd->extract() to write up to 32 KiB of stale heap memory into extracted output.

Weakness: CWE-908 (Use of Uninitialized Resource)

## Which versions are affected by CVE-2026-119602?


## How do I fix CVE-2026-119602?

No fix has been published for CVE-2026-119602 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-119602 being exploited?

There is no known exploitation of CVE-2026-119602 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-119602 and fix it if it is affected.

What it is: CVE-2026-119602 is a medium-severity vulnerability in kyz libmspack, published on 30 Oct 2026. 
Exploitation: There is no known exploitation of CVE-2026-119602 in the wild and no public exploit code.

Affected product: kyz libmspack. 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-2026-119602/ (Markdown: https://insights.sbomify.com/CVE-2026-119602/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-119602
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-119602
- OSV: https://osv.dev/vulnerability/CVE-2026-119602

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-119602/
Summaries are generated and may contain mistakes; the official description above is the record.