CVE-2026-125174 (CVSS 5.5)

Description

FFmpeg before 8.1.3 and 9.x before 9.0.2 contains a NULL pointer dereference vulnerability in ff_hap_set_chunk_count() in libavcodec/hap.c, where a shadowed return variable masks reallocation failures. Attackers can supply a crafted Hap video frame with an oversized chunk count so the decoder writes through a NULL chunk table, crashing the application.

Is your site exposed to CVE-2026-125174?

Run a free security scan — no signup, results in seconds.

CVSS v3.1 Score

5.5

MEDIUM

CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H

EPSS — Exploit Prediction

0.0018

Probability of exploitation

0.08%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-252 CWE-252

References

Other References

https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/24487 https://github.com/FFmpeg/FFmpeg https://github.com/FFmpeg/FFmpeg/blob/n9.0.1/libavcodec/hap.c#L33 https://github.com/FFmpeg/FFmpeg/commit/f8c4c6400e835bf65e8b9cc12aba9e5c4d1c818c https://www.vulncheck.com/advisories/ffmpeg-before-8.1.3-and-9-x-before-9.0.2-null-pointer-dereference-via-ff-hap-set-chunk-count

Frequently Asked Questions

What is CVE-2026-125174? +

FFmpeg before 8.1.3 and 9.x before 9.0.2 contains a NULL pointer dereference vulnerability in ff_hap_set_chunk_count() in libavcodec/hap.c, where a shadowed return variable masks reallocation failures. Attackers can supply a crafted Hap video frame with an oversized chunk count so the decoder writes through a NULL chunk table, crashing the application. It has a CVSS v3.1 base score of 5.5 (MEDIUM).

How severe is CVE-2026-125174? +

CVE-2026-125174 has a CVSS v3.1 score of 5.5 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance. The EPSS score is 0.0018, placing it in the 0th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2026-125174? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

Related Vulnerabilities

CVE-2026-78699

Unchecked Return Value vulnerability in ash-project ash_postgres allows a user who can drive a tenant rename to a name that …

CVE-2026-62930

Unchecked return value in the MigTD's TLS implementation for the Intel(R) TDX Migration Trust Domain (MigTD) within Ring 0: Hypervisor …

CVE-2025-29938

An unchecked return value within the AMD Platform Management Framework (PMF) could allow an attacker to write to an arbitrary …

CVE-2025-0028

An unchecked return value within the AMD Platform Management Framework (PMF) could allow an attacker to read or modify an …

CVE-2025-1394

The Ember ZNet stack’s packet buffer manager may read out of bound memory leading to an assert, causing a Denial …

CVE-2026-90648

wasm2c in WebAssembly wabt through 1.0.41 allows sandbox escape in some situations that primarily involve 32-bit platforms, aka a "table …

CVE-2026-125174