CVE-2026-53703 | Gstreamer1-plugins-ugly-free: gstreamer: out-of-bounds read in realmedia demuxer audio stream header parser

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.

Published: 2026-06-15 Last update: 2026-06-17 Assigner: [email protected] Source: [email protected]
NVD Status：Awaiting Analysis，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-53703 is rated Low Risk (31.5/100): CVSS High severity, with low exploitation likelihood (EPSS 0.19%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-53703

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-16 — 0.19% —

Full EPSS history (1 record total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-53703

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.1 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 2.8 4.2 [email protected]

Weakness enumeration for CVE-2026-53703

GitHub Security Advisory for CVE-2026-53703

GHSA-hghw-p2mw-fvch · Severity: high — A vulnerability was found in the GStreamer RealMedia demuxer (gst-plugins-ugly). When processing...

OS Trackers for CVE-2026-53703

vendor priority summary link
debian not yet assigned CVE-2026-53703 not yet assigned priority: Debian including 1 source packages (gst-plugins-ugly1.0), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): open 3, resolved 2. https://security-tracker.debian.org/tracker/CVE-2026-53703
suse high — https://www.suse.com/security/cve/CVE-2026-53703/
ubuntu medium CVE-2026-53703 medium priority: Ubuntu including 1 source packages (gst-plugins-ugly1.0), 7 status rows across 7 suites (bionic, focal, jammy, noble, questing, resolute, upstream): needs-triage 6, released 1. https://ubuntu.com/security/CVE-2026-53703

Affected software / configurations for CVE-2026-53703

Vendor Product Version Raw CPE
No affected products in dataset.

References for CVE-2026-53703

cvelogic Threat Intelligence