CVSS 4.0
7.7 highCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:PCVE-2026-23534
High (7.7) in freerdp freerdp. EPSS 0.5% chance of exploitation in the next 30 days.
FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to version 3.21.0, a client-side heap buffer overflow occurs in the ClearCodec bands decode path when crafted band coordinates allow writes past the end of the destination surface buffer. A malicious server can trigger a client‑side heap buffer overflow, causing a crash (DoS) and potential heap corruption with code‑execution risk depending on allocator behavior and surrounding heap layout. Version 3.21.0 contains a patch for the issue.
Severity
CVSS 3.1
9.8 criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H- EPSS
- 0.5% chance of exploitation in the next 30 days; higher than 45% of CVEs (scores of 2026-11-01)
- CWE
- CWE-122
- Published
- Modified
- Record from
- the NVD, synced
Affected
- freerdp:freerdp
References
- https://github.com/FreeRDP/FreeRDP/blob/38514dfa5813aa945a86cfbcec279033f8394468/libfreerdp/codec/clear.c#L878-L879
- https://github.com/FreeRDP/FreeRDP/blob/38514dfa5813aa945a86cfbcec279033f8394468/libfreerdp/codec/clear.c#L883-L884
- https://github.com/FreeRDP/FreeRDP/releases/tag/3.21.0
- https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-3frr-mp8w-4599
- https://access.redhat.com/errata/RHSA-2026:2048