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Fencer Vulns
low 3.1

CVE-2020-4033 json

OOB Read in RLEDECOMPRESS in FreeRDP

published 2020-06-22 6 y ago modified 2026-06-17 4 mo ago also EUVD-2020-25298

cvss
3.1
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
1.8%
EPSS 1.8% chance of exploitation in 30 days, percentile 78%
public exploits
0
none known

Summary

In FreeRDP before version 2.1.2, there is an out of bounds read in RLEDECOMPRESS. All FreeRDP based clients with sessions with color depth < 32 are affected. This is fixed in version 2.1.2.

Patch / fix

  • freerdp freerdp 2.1.2
  • freerdp2 Debian 12 2.1.2+dfsg1-1

debian advisories DEBIAN-CVE-2020-4033

  • freerdp2 Ubuntu 18.04 LTS 2.2.0+dfsg1-0ubuntu0.18.04.1
  • freerdp2 Ubuntu 20.04 LTS 2.2.0+dfsg1-0ubuntu0.20.04.1

ubuntu advisories UBUNTU-CVE-2020-4033

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

  • freerdp RHEL 8 2:2.2.0-1.el8
  • libwinpr RHEL 8 2:2.2.0-1.el8
  • freerdp-libs RHEL 8 2:2.2.0-1.el8

red hat advisories RHSA-2021:1849

  • freerdp SLE Workstation Extension 12 SP5, SLE Software Development Kit 12 SP5 2.1.2-12.20.1
  • vinagre SLE Workstation Extension 12 SP5 3.20.2-16.3.3
  • freerdp SLE Workstation Extension 15 SP2 2.1.2-15.7.1
  • freerdp SLE Workstation Extension 15 SP1 2.1.2-10.15.1

suse advisories SUSE-SU-2020:2272-1SUSE-SU-2020:2068-1SUSE-SU-2020:2032-1

  • freerdp2 openSUSE Tumbleweed 2.4.0-2.1
  • freerdp openSUSE Leap 15.1 2.1.2-lp151.5.6.1

opensuse advisories openSUSE-SU-2024:10768-1openSUSE-SU-2020:1090-1

  • freerdp Rocky Linux 8 2:2.2.0-1.el8
  • freerdp Rocky Linux 8 2:2.2.0-10.el8

rocky linux advisories RLSA-2021:1849

  • freerdp Alpine 3.24, Alpine 3.23, Alpine 3.22 +10 more 2.1.2-r0
  • freerdp2 Alpine 3.24, Alpine 3.23, Alpine 3.22 2.1.2-r0

alpine advisories ALPINE-CVE-2020-4033

Alpine secdb © Alpine Linux, from https://secdb.alpinelinux.org via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

  • freerdp Arch Linux 2:2.1.2-1

arch linux advisories AVG-1193

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-2020-4033 updated cvss 6.5

freerdp: out-of-bounds read in RLEDECOMPRESS

  • Red Hat Enterprise Linux 6 freerdp, freerdp-libs, freerdp-plugins
    affected: workaround, no fix planned “Set the color depth to 32 with the client commandline option: /bpp:32.”
  • Red Hat Enterprise Linux 7 freerdp, libwinpr, freerdp-libs, freerdp-plugins
    affected: workaround, no fix available “Set the color depth to 32 with the client commandline option: /bpp:32.”
  • Red Hat CodeReady Linux Builder (v. 8) freerdp-devel 2.2.0-1.el8, freerdp-debuginfo 2.2.0-1.el8, libwinpr-debuginfo 2.2.0-1.el8, freerdp-debugsource 2.2.0-1.el8, freerdp-libs-debuginfo 2.2.0-1.el8 Red Hat Enterprise Linux AppStream (v. 8) freerdp 2.2.0-1.el8, libwinpr 2.2.0-1.el8, freerdp-libs 2.2.0-1.el8
    fixed: vendor fix “Set the color depth to 32 with the client commandline option: /bpp:32.” RHSA-2021:1849

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

Exploit prediction

1.81% chance of exploitation in the next 30 days, higher than 78% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CNA 3.1 3.1 CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:N
NVD 3.1 6.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L
NVD 2.0 6.4 AV:N/AC:L/Au:N/C:P/I:N/A:P

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.