CVE-2026-53704 Gstreamer1-plugins-ugly-free: gstreamer: out-of-bounds read in realmedia demuxer fileinfo metadata parser
A crafted RealMedia file can cause a crash, hang, or limited memory disclosure in GStreamer's RealMedia demuxer due to missing bounds checks.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2026-53704?
CVE-2026-53704 is a high-severity memory corruption vulnerability in Red Hat Enterprise Linux 10, published on 15 Jun 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
A flaw was found in GStreamer's RealMedia demuxer in the gst-plugins-ugly package. When processing a RealMedia file containing a specially crafted FILEINFO metadata section, the demuxer parses variable-name and variable-value pairs using re_skip_pascal_string() without validating that offsets remain within the mapped buffer. Additionally, the element count controlling the parsing loop is read from attacker-controlled data without validation, which can cause an infinite loop. A crafted RealMedia file can cause the application to crash, hang, or potentially read limited adjacent memory contents.
Weakness: CWE-125
Which versions are affected by CVE-2026-53704?
How do I fix CVE-2026-53704?
Apply the vendor's patch.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2026-53704 being exploited?
There is no known exploitation of CVE-2026-53704 in the wild and no public exploit code.
Sources
Also known as DEBIAN-CVE-2026-53704, GHSA-j3jj-fwr8-4v9m, UBUNTU-CVE-2026-53704.