---
id: "CVE-2026-125064"
page: "https://infrastack.ai/live/CVE-2026-125064"
kind: "vulnerability"
aliases: ["CVE-2026-125064"]
title: "FFmpeg: crafted AVI file crashes the decoder via NULL pointer dereference"
severity: "medium"
cvss: 6.8
epss: null
exploited: false
status: "open"
category: "package"
products: []
ecosystems: []
tags: ["ffmpeg", "libavcodec", "media-processing", "package"]
not_affected_if: ["g726-not-decoded", "no-untrusted-media"]
published_at: "2026-11-09T19:16:48+00:00"
first_seen_at: "2026-11-09T19:28:15+00:00"
updated_at: "2026-11-09T19:31:49+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-125064", "first_seen_at": "2026-11-09T19:28:15+00:00"}]
exploit_sources: []
---

# FFmpeg: crafted AVI file crashes the decoder via NULL pointer dereference

Link for people: https://infrastack.ai/live/CVE-2026-125064 (this .md is for agents)

FFmpeg's G.726 audio decoder in libavcodec ignores a failed buffer setup when given an oversized packet. A crafted AVI file with a very large G.726 audio chunk makes the process read from a NULL buffer and crash.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Run `ffmpeg -version` and compare against the fixed release in the sources, which the sources do not state: unknown
- Check whether your application decodes untrusted AVI files with G.726 audio through libavcodec

## Fix

- FFmpeg: unknown; a patch is linked from the sources (github.com), but the fixed version is not stated

## Timeline

- 2026-11-09T19:28:15+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-125064

## Documents

- [advisory] Third-party advisory: www.vulncheck.com https://www.vulncheck.com/advisories/ffmpeg-through-9.0.2-null-pointer-dereference-in-g-726-adpcm-decoder
- [fix] Patch: github.com https://github.com/FFmpeg/FFmpeg/commit/ec887b13a88afbaf44fb28c3045bda5d434da8dc

## From the sources

FFmpeg through 9.0.2 contains a NULL pointer dereference vulnerability in g726_decode_frame() in libavcodec/g726.c because it ignores init_get_bits() failure on oversized packets. Attackers can supply a crafted AVI file with a 268435392-byte G.726 audio chunk to make the decoder read from a NULL buffer, crashing the process.

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_Free to read, with fair use of about 60 pages a minute. For higher limits or API access: sales@infrastack.ai_