High severity · published May 29, 2026
CVE-2026-44420
FreeRDP cliprdr server heap-buffer-overflow via undersized capabilitySetLength in CB_CLIP_CAPS
8.8
CVSS
4.6%
EPSS
No
On KEV
Description
FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.26.0, a malicious RDP client can trigger a heap-buffer-overflow write in FreeRDP's server-side clipboard (cliprdr) channel by sending a CB_CLIP_CAPS PDU with a too-small capabilitySetLength. This can crash the server process (remote DoS) and may be exploitable for code execution because it corrupts heap memory. This vulnerability is fixed in 3.26.0.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)4.6% · higher than 92% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
FR
FreeRDP · FreeRDP
< 3.26.0 · source: vendor, NVD
RH
Red Hat Enterprise Linux 10 · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Enterprise Linux 6 · Red Hat
All versions, or not specified · source: CISA
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-44420
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-44420
Exploit
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-mvpx-xj7r-3p3r
access.redhat.com
https://access.redhat.com/errata/RHSA-2026:36203
access.redhat.com
https://access.redhat.com/errata/RHSA-2026:46393
access.redhat.com
https://access.redhat.com/security/cve/CVE-2026-44420
bugzilla.redhat.com
https://bugzilla.redhat.com/show_bug.cgi?id=2483480
github.com
https://github.com/yhirose/cpp-httplib/security/advisories/GHSA-h6wq-j5mv-f3q8
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