Executive brief
GStreamer is a widely used multimedia framework that allows applications to process audio and video. A vulnerability in how it handles DVB subtitles could allow an attacker to execute malicious code if a user opens a specially crafted media file. This could lead to a full system compromise or unauthorized access to sensitive data on the user's machine.
Technical details
An out-of-bounds write vulnerability exists in GStreamer's dvbsuboverlay component due to insufficient validation of user-supplied coordinate data within DVB subtitle segments. Specifically, the flaw occurs in the _dvb_sub_parse_clut_segment and related parsing functions where missing bounds checks allow data to be written past the end of an allocated buffer. An attacker can exploit this by providing a malicious media file containing crafted DVB subtitle metadata. Successful exploitation requires a user to interact with the library (e.g., by opening the file in a media player using GStreamer) and can result in arbitrary code execution in the context of the current process. A patch has been released in the GStreamer git repository (commit 3b8253f4).
Affected products
- GStreamer GStreamer All versions prior to commit 3b8253f4
- Red Hat Enterprise Linux AppStream (v. 8)
- Red Hat Enterprise Linux AppStream (v. 9)
- Red Hat Enterprise Linux AppStream (v. 10)
Timeline
- 2026-02-11: disclosed: Vulnerability reported to vendor
- 2026-02-25: patched: Fix committed to GStreamer repository
- 2026-03-06: advisory: Coordinated public release by Zero Day Initiative
- 2026-03-16: advisory: Published to NVD
References
- https://gitlab.freedesktop.org/gstreamer/gstreamer/-/commit/3b8253f447bcc9831dbf643d2c69b205fedbe086
- https://www.zerodayinitiative.com/advisories/ZDI-26-161/
- https://access.redhat.com/errata/RHSA-2026:19024
- https://access.redhat.com/errata/RHSA-2026:19180
- https://access.redhat.com/errata/RHSA-2026:6259
- https://access.redhat.com/errata/RHSA-2026:6300
- https://access.redhat.com/errata/RHSA-2026:6750