CVE-2026-53703

GStreamer is a streaming media framework, based on graphs of elements which operate on media data. This package contains plug-ins whose license is not fully compatible with LGPL.

Security Fix(es):

• gstreamer1-plugins-ugly-free: GStreamer: Out-of-bounds read in RealMedia demuxer audio stream header parser (CVE-2026-53703)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

GStreamer is a streaming media framework, based on graphs of elements which operate on media data. This package contains plug-ins whose license is not fully compatible with LGPL.

Security Fix(es):

• gstreamer1-plugins-ugly-free: GStreamer: Out-of-bounds read in RealMedia demuxer audio stream header parser (CVE-2026-53703)

• gstreamer1-plugins-ugly-free: GStreamer: Out-of-bounds read in RealMedia demuxer FILEINFO metadata parser (CVE-2026-53704)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

A vulnerability was found in the GStreamer RealMedia demuxer (gst-plugins-ugly). When processing a RealMedia (.rm) file, the demuxer parses MDPR (media properties) chunks to configure audio streams. For audio stream header versions 4 and 5, the parser reads fields such as codec type, packet size, sample rate, channel count, and extra codec data length from fixed offsets within the chunk without first checking that the chunk contains enough data. If a malicious file provides an MDPR chunk that is too small to contain a complete audio stream header, the parser reads beyond the end of the buffer. This can cause the application to crash. In some cases, bytes read past the buffer boundary may be incorporated into stream metadata, which could result in limited information disclosure.

GStreamer is a streaming media framework, based on graphs of elements which operate on media data. This package contains plug-ins whose license is not fully compatible with LGPL.

Security Fix(es):

• gstreamer1-plugins-ugly-free: GStreamer: Out-of-bounds read in RealMedia demuxer audio stream header parser (CVE-2026-53703)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

GStreamer is a streaming media framework, based on graphs of elements which operate on media data. This package contains plug-ins whose license is not fully compatible with LGPL.

Security Fix(es):

• gstreamer1-plugins-ugly-free: GStreamer: Out-of-bounds read in RealMedia demuxer audio stream header parser (CVE-2026-53703)
• gstreamer1-plugins-ugly-free: GStreamer: Out-of-bounds read in RealMedia demuxer FILEINFO metadata parser (CVE-2026-53704)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

• CVE-2026-53703: fix rmdemux out-of-bounds read parsing MDPR audio header
• CVE-2026-53704: fix rmdemux security issues in FILEINFO/pascal-string parsing

Michael Randrianantenaina discovered that GStreamer's Ugly Plugins incorrectly handled certain malformed RealMedia files. If a user were tricked into opening a crafted media file, an attacker could possibly use this issue to execute arbitrary code. This issue only affected Ubuntu 16.04 LTS, Ubuntu 18.04 LTS, Ubuntu 20.04 LTS and Ubuntu 22.04 LTS. (CVE-2023-38103, CVE-2023-38104)

It was discovered that GStreamer's Ugly Plugins incorrectly handled certain malformed ASF and RealMedia files. If a user were tricked into opening a crafted media file, an attacker could possibly use this issue to execute arbitrary code. This issue only affected Ubuntu 16.04 LTS, Ubuntu 18.04 LTS, Ubuntu 20.04 LTS and Ubuntu 22.04 LTS and Ubuntu 24.04 LTS. (CVE-2026-2920, CVE-2026-2922)

Tianshuo Han discovered that GStreamer's Ugly Plugins incorrectly handled certain malformed RealMedia files. If a user were tricked into opening a crafted media file, an attacker could possibly use this issue to cause a denial of service or expose sensitive information. (CVE-2026-53703, CVE-2026-53704)

Seonwook Kim discovered that GStreamer's Ugly Plugins incorrectly handled certain malformed ASF files. If a user were tricked into opening a crafted media file, an attacker could possibly use this issue to cause a denial of service or expose sensitive information. (CVE-2026-19389)