# CVE-2026-76886: Heap-based Buffer Overflow in Wireshark

> A heap-based buffer overflow in the C12.22 dissector allows attackers to cause a denial of service via crafted packets.

- **Severity:** High 8.1 (`CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 19 Aug 2026
- **Updated:** 20 Aug 2026
- **Also known as:** AZL-96779, CLSA-2026-1792635672, DEBIAN-CVE-2026-76886, GHSA-wrhv-64xq-9g54, MINI-6mxm-rgwr-4fx9, UBUNTU-CVE-2026-76886

## What is CVE-2026-76886?

CVE-2026-76886 is a high-severity memory corruption vulnerability in Wireshark Wireshark, published on 19 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

C12.22 protocol dissector crash in 4.6.0 to 4.6.7 and 4.4.0 to 4.4.18 allows denial of service

Weakness: CWE-122 (Heap-based Buffer Overflow)

## Which versions are affected by CVE-2026-76886?

It affects 1 product.


Products: Wireshark Wireshark.

## How do I fix CVE-2026-76886?

Upgrade to a fixed version.

## Is CVE-2026-76886 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-76886 exists.

## Other vulnerabilities in Wireshark Wireshark

- [CVE-2011-0444](https://insights.sbomify.com/CVE-2011-0444/): Memory corruption in n/a (critical 10.0)
- [CVE-2010-2994](https://insights.sbomify.com/CVE-2010-2994/): Memory corruption in n/a (critical 10.0)
- [CVE-2010-2995](https://insights.sbomify.com/CVE-2010-2995/): Memory corruption in n/a (critical 10.0)
- [CVE-2009-1266](https://insights.sbomify.com/CVE-2009-1266/): Other in n/a (critical 10.0)
- [CVE-2009-1210](https://insights.sbomify.com/CVE-2009-1210/): Memory corruption in n/a (critical 10.0)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-76886 and fix it if it is affected.

What it is: CVE-2026-76886 is a high-severity memory corruption vulnerability in Wireshark Wireshark, published on 19 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-76886 exists.

Affected product: Wireshark Wireshark. 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-2026-76886/ (Markdown: https://insights.sbomify.com/CVE-2026-76886/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-76886
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-76886
- OSV: https://osv.dev/vulnerability/CVE-2026-76886

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-76886/
Summaries are generated and may contain mistakes; the official description above is the record.