# CVE-2026-3707: MrNanko webp4j gif_decoder.c DecodeGifFromMemory integer overflow

> An integer overflow in webp4j's GIF decoder allows local attackers to cause a denial of service via crafted input.

- **Severity:** Medium 4.8 (`CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P`)
- **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:** No
- **Published:** 8 Mar 2026
- **Updated:** 10 Mar 2026
- **Also known as:** GHSA-vhg7-ppx8-v8hh

## What is CVE-2026-3707?

CVE-2026-3707 is a medium-severity vulnerability in MrNanko webp4j, published on 8 Mar 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

A vulnerability was identified in MrNanko webp4j up to 1.3.x. The affected element is the function DecodeGifFromMemory of the file src/main/c/gif_decoder.c. Such manipulation of the argument canvas_height leads to integer overflow. Local access is required to approach this attack. The exploit is publicly available and might be used. The name of the patch is 89771b201c66d15d29e4cc016d8aae82b6a5fbe1. It is advisable to implement a patch to correct this issue.

Weakness: CWE-190 (Integer Overflow or Wraparound), CWE-189

## Which versions are affected by CVE-2026-3707?


## How do I fix CVE-2026-3707?

No fix has been published for CVE-2026-3707 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-3707 being exploited?

There is no known exploitation of CVE-2026-3707 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-3707 and fix it if it is affected.

What it is: CVE-2026-3707 is a medium-severity vulnerability in MrNanko webp4j, published on 8 Mar 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-2026-3707 in the wild and no public exploit code.

Affected product: MrNanko webp4j. 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-2026-3707/ (Markdown: https://insights.sbomify.com/CVE-2026-3707/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-3707
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-3707
- OSV: https://osv.dev/vulnerability/CVE-2026-3707

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-3707/
Summaries are generated and may contain mistakes; the official description above is the record.