CVE-2026-23534
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.
CVSS
- Versión: 4.0
- Vector: CVSS: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:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
- Puntuación base: 7.7
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.52%
- Percentil entre todas las CVEs puntuadas: 42
- Fecha de la puntuación: 5/10/2026
EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).
🎯 Técnicas ATT&CK
Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.
- Explotación
T1190Exploit Public-Facing Applicationinitial access85 % - Impacto principal
T1499.004Application or System Exploitationimpact80 % - Impacto secundario
T1068Exploitation for Privilege Escalationprivilege escalation65 %
Vector AV:N/PR:N/UI:N indica explotación remota sin privilegios (T1190). Servidor malicioso explota desbordamiento de buffer en cliente RDP causando DoS (T1499.004) y potencial corrupción de heap con riesgo de ejecución de código (T1068).
Inferido por nuestro agente de análisis a partir de la descripción oficial, el vector CVSS y la CWE, y comprobado por un supervisor. Puede contener errores.
🛡️ Mitigaciones ATT&CK que cubren estas técnicas
Tecnologías afectadas (1)
CWE
- CWE-122
- CWE-122
Referencias
- 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
- https://access.redhat.com/errata/RHSA-2026:2081
- https://access.redhat.com/errata/RHSA-2026:2222
- https://access.redhat.com/errata/RHSA-2026:2736
- https://access.redhat.com/errata/RHSA-2026:2952
- https://access.redhat.com/errata/RHSA-2026:3037
- https://access.redhat.com/security/cve/CVE-2026-23534
- https://bugzilla.redhat.com/show_bug.cgi?id=2430888
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-23534.json
JSON original (NVD)
Mostrar
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