CVE-2026-33952 (GCVE-0-2026-33952)
Vulnerability from cvelistv5 – Published: 2026-03-30 21:42 – Updated: 2026-04-02 14:11
VLAI
EPSS
VEX
Title
FreeRDP: DoS via WINPR_ASSERT in rts_read_auth_verifier_no_checks
Summary
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.
Severity
SSVC
Exploitation: poc
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-04-02 14:11 UTC
CWE
- CWE-617 - Reachable Assertion
Assigner
GitHub_M
CNA
References
2 references
| URL | Tags |
|---|---|
| https://github.com/FreeRDP/FreeRDP/security/advis… | x_refsource_CONFIRM |
| https://github.com/FreeRDP/FreeRDP/commit/4ac0b64… | x_refsource_MISC |
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