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Fencer Intel
medium 6.1

CVE-2026-121601 json

Gstreamer1-plugins-bad-free: gstreamer1-plugins-bad-free: out-of-bounds read in mxfdemux via unchecked delta_id and slice index

published 2d ago modified 2d ago also EUVD-2026-120051

cvss
6.1
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.2%
EPSS 0.2% chance of exploitation in 30 days, percentile 5%
public exploits
0
none known

Summary

A flaw was found in GStreamer's MXF demuxer plugin (gst-plugins-bad). When processing a specially crafted MXF media file, the demuxer indexes its internal delta-entry and slice-offset tables using values from the file without validating that they are within the bounds of the allocated arrays. A local attacker who tricks a user into opening a malicious MXF file can cause the application to crash (denial of service) and may be able to read limited amounts of heap memory adjacent to the affected arrays.

Patch / fix

  • gst-plugins-bad1.0 Debian 14 1.28.9-1

debian advisories DEBIAN-CVE-2026-121601

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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-2026-121601 updated cvss 6.1

gstreamer1-plugins-bad-free: gstreamer1-plugins-bad-free: Out-of-bounds read in mxfdemux via unchecked delta_id and slice index

  • Red Hat Enterprise Linux 9 gstreamer1-plugins-bad-free, gstreamer1-plugins-bad-free-libs Red Hat Enterprise Linux 10 gstreamer1-plugins-bad-free
    affected: workaround, no fix available “Mitigation is to avoid parsing untrusted MXF content with the GStreamer MXF demuxer until a fixed package is available, or to disable the mxfdemux plugin where the application allows plugin selection.”
  • Red Hat Enterprise Linux 6 gstreamer-plugins-bad-free, gstreamer-plugins-bad-free-extras Red Hat Enterprise Linux 7 gstreamer-plugins-bad-free, gstreamer1-plugins-bad-free, gstreamer1-plugins-bad-free-gtk Red Hat Enterprise Linux 8 gstreamer1-plugins-bad-free
    not affected: vulnerable code not present

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
2d ago

Exploit prediction

0.16% chance of exploitation in the next 30 days, higher than 5% of all scored CVEs (FIRST EPSS, 2026-11-11).

CVSS scores

assigned by version score vector
CNA 3.1 6.1 CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:H

Affected products

  • Red Hat Red Hat Enterprise Linux 10
  • Red Hat Red Hat Enterprise Linux 6
  • Red Hat Red Hat Enterprise Linux 7
  • Red Hat Red Hat Enterprise Linux 8
  • Red Hat Red Hat Enterprise Linux 9

Classification

Weakness

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.