Is CVE-2026-121611 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-121611 being exploited in the wild.

How severe is CVE-2026-121611?

Medium severity, with a CVSS score of 6.5, published 9 November 2026.

Which products and versions are affected?

Gstreamer Gst-Plugins-Bad 1.16.0 through prior to 1.28.9.

Is there a fix for CVE-2026-121611?

No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

How is CVE-2026-121611 attacked?

It is attacked over the network, in a software library.

Am I affected by CVE-2026-121611?

Check whether you run Gstreamer Gst-Plugins-Bad at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-121611: GStreamer gst-plugins-bad H.265 uninitialized memory use

CVE-2026-121611 · Severity: medium · CVSS 6.5 · Published 2026-11-09

GStreamer is a multimedia framework used by applications to play audio and video content. A vulnerability in the H.265 video codec parser allows a remote attacker to crash applications by sending a specially crafted video file with malformed codec parameters. An attacker could exploit this to cause denial of service against any application using GStreamer to play H.265 video content.

Technologies: Gstreamer Gst-Plugins-Bad. Vendors: Gstreamer.

Quick answers

Is CVE-2026-121611 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-121611 being exploited in the wild.
How severe is CVE-2026-121611?: Medium severity, with a CVSS score of 6.5, published 9 November 2026.
Which products and versions are affected?: Gstreamer Gst-Plugins-Bad 1.16.0 through prior to 1.28.9.
Is there a fix for CVE-2026-121611?: No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is CVE-2026-121611 attacked?: It is attacked over the network, in a software library.
Am I affected by CVE-2026-121611?: Check whether you run Gstreamer Gst-Plugins-Bad at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

A use-of-uninitialized-memory flaw exists in the H.265 (HEVC) bitstream parser when processing Video Parameter Sets that declare multiple HRD (Hypothetical Reference Decoder) parameter sets. An attacker can trigger this by providing a crafted H.265 media file or stream processed by an application using the vulnerable library, causing unpredictable parser behavior and application crashes with no code execution possible.

Affected products

GStreamer gst-plugins-bad 1.16.0 through prior to 1.28.9

Timeline

2026-11-09: disclosed

References

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