Medium severity · published Mar 30, 2026
CVE-2026-33952
FreeRDP: DoS via WINPR_ASSERT in rts_read_auth_verifier_no_checks
6.5
CVSS
0.3%
EPSS
No
On KEV
Description
FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to version 3.24.2, an unvalidated auth_length field read from the network triggers a WINPR_ASSERT() failure in rts_read_auth_verifier_no_checks(), causing any FreeRDP client connecting through a malicious RDP Gateway to crash with SIGABRT. This is a pre-authentication denial of service affecting all FreeRDP clients using RPC-over-HTTP gateway transport. The assertion is active in default release builds (WITH_VERBOSE_WINPR_ASSERT=ON). This issue has been patched in version 3.24.2.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 21% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
FR
FreeRDP · FreeRDP
< 3.24.2 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-33952
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-33952
Patch
https://github.com/FreeRDP/FreeRDP/commit/4ac0b6467d371a1ad47c1f751c5b305e4c068adb
Exploit
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-4v4p-9v5x-hc93
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