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Fencer Vulns
low 2.1

CVE-2026-66401 json

FreeRDP before 3.29.0 Out-of-Bounds Read via UVC H.264

published 2026-08-01 3 mo ago modified 2026-09-03 2 mo ago also EUVD-2026-51831

cvss
2.1
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 10%
public exploits
0
none known

Summary

FreeRDP before 3.29.0 contains an out-of-bounds heap read vulnerability in the UVC H.264 extension-unit parser that fails to validate descriptor length before accessing the GUID field. A local attacker with a malicious USB video camera can trigger a heap read beyond allocated bounds during camera stream setup, causing denial of service.

Patch / fix

  • FreeRDP FreeRDP 3.29.0
  • freerdp3 Debian 14 3.29.0+dfsg-1

debian advisories DEBIAN-CVE-2026-66401

  • freerdp3 Ubuntu 24.04 LTS 3.30.0+dfsg-0ubuntu0.24.04.1
  • freerdp3 Ubuntu 26.04 LTS 3.30.0+dfsg-0ubuntu0.26.04.1

ubuntu advisories UBUNTU-CVE-2026-66401

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

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-2026-66401 updated cvss 2.1

FreeRDP: FreeRDP: Denial of Service via out-of-bounds read in UVC H.264 parser

  • Red Hat Enterprise Linux 6 freerdp, freerdp-libs, freerdp-plugins Red Hat Enterprise Linux 7 freerdp, libwinpr, freerdp-libs, freerdp-plugins
    affected: no fix planned “Out of support scope”
  • Red Hat Enterprise Linux 8 freerdp, libwinpr, freerdp-libs Red Hat Enterprise Linux 9 freerdp, libwinpr, freerdp-libs Red Hat Enterprise Linux 10 freerdp
    affected: 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
Proof of concept is public
Automatable
no
Technical impact
partial
Assessed
3 mo ago

Exploit prediction

0.20% chance of exploitation in the next 30 days, higher than 10% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

  • github.com https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-8jj2-67pg-j6mg referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 4.0 2.4 CVSS:4.0/AV:P/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
CNA 3.1 2.1 CVSS:3.1/AV:P/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L
CNA 4.0 2.4 CVSS:4.0/AV:P/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Affected products

  • FreeRDP FreeRDP

Classification

Weakness

References

Sources

Fencer Vulns 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.