Bug 2487614 (CVE-2026-53704)

Summary:	CVE-2026-53704 gstreamer1-plugins-ugly-free: GStreamer: Out-of-bounds read in RealMedia demuxer FILEINFO metadata parser
Product:	[Other] Security Response	Reporter:	OSIDB Bzimport <bzimport>
Component:	vulnerability	Assignee:	Product Security <prodsec-ir-bot>
Status:	NEW ---	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	rhel-process-autobot, security-response-team, watson-tool-maintainers
Target Milestone:	---	Keywords:	Security
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Hardware:	All
OS:	Linux
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Doc Text:	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.	Story Points:	---
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oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:
Bug Depends On:	2488945
Bug Blocks:

Description OSIDB Bzimport 2026-06-10 16:15:15 UTC

GStreamer RealMedia demuxer FILEINFO metadata OOB read. In gst_rmdemux_parse_mdpr(), the FILEINFO parsing loop (while element_nb) advances offset using re_skip_pascal_string() without bounds checking. re_skip_pascal_string() reads a length byte at the current offset and returns offset + 1 + length without validating the buffer boundary. element_nb is attacker-controlled and stored as signed int; value 0xFFFFFFFF causes infinite loop. No fix available; upstream recommends rmdemux rewrite. Reported via PSIRTSUPT-7239 by Tianshuo Han.