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Fencer Intel
medium 6.5

CVE-2026-125040 json

Gst-plugins-base: gst-plugins-base: quadratic regex processing in srt/webvtt subtitle parser causes denial of service

published 5h ago modified 4h ago also EUVD-2026-120150

cvss
6.5
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
—
no EPSS score yet
public exploits
0
none known

Summary

A flaw was found in the SRT and WebVTT subtitle parser in GStreamer's gst-plugins-base. While sanitizing inline subtitle markup, the parser repeatedly searches the remaining text with unanchored regular expressions. A crafted subtitle cue with a long line of unmatched markup-like text can force quadratic CPU use and make a GStreamer-based application unresponsive.

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Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-125040 updated cvss 6.5

gst-plugins-base: gst-plugins-base: Quadratic regex processing in SRT/WebVTT subtitle parser causes denial of service

  • Red Hat Enterprise Linux 7 gstreamer1-plugins-base, gstreamer1-plugins-base-tools Red Hat Enterprise Linux 8 gstreamer1-plugins-base Red Hat Enterprise Linux 9 gstreamer1-plugins-base, gstreamer1-plugins-base-tools Red Hat Enterprise Linux 10 gstreamer1-plugins-base
    affected: workaround, no fix available “Fix deferred”

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
5h ago

CVSS scores

assigned by version score vector
CNA 3.1 6.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
NVD 3.1 6.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H

Affected products

  • Red Hat Red Hat Enterprise Linux 10
  • Red Hat Red Hat Enterprise Linux 7
  • Red Hat Red Hat Enterprise Linux 8
  • Red Hat Red Hat Enterprise Linux 9

Classification

Weakness
  • CWE-1333 Inefficient Regular Expression Complexity

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.