Buffer overflow in Gstreamer

CVE-2026-5056

GStreamer qtdemux Stack-based Buffer Overflow Remote Code Execution Vulnerability. This vulnerability allows remote attackers to execute arbitrary code on affected installations of GStreamer. Interaction with this library is required to exploit this vulnerability but attack vectors may vary depending on the implementation. The specific flaw exists within the parsing of UncompressedFrameConfigBox structures. The issue results from the lack of proper validation of the length of user-supplied data prior to copying it to a fixed-length stack-based buffer. An attacker can leverage this vulnerability to execute code in the context of the current process. Was ZDI-CAN-29392.

Vulnerability class: Buffer Overflow

EPSS: 0.004 (33.3th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.8 (High). Vector: CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H.

Affected products

  • Gstreamer — versions a303670510771b993867ddf62bff3bce0cb988c3

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-5056?
CVE-2026-5056 is a high-severity vulnerability in Gstreamer, classified under Stack-based Buffer Overflow. CVSS score: 7.8/10. Published 2026-07-29.
How severe is CVE-2026-5056?
High severity. CVSS v3 base score is 7.8 out of 10.