{"id":"CVE-2026-23534","title":"FreeRDP is a free implementation of the Remote Desktop Protocol","summary":"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 destin…","severity":"critical","cvss":9.8,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","cwe":["CWE-122","CWE-122"],"vendor":"freerdp","product":"freerdp","affected":["freerdp < 3.21.0"],"patched":["freerdp 3.21.0"],"published":"2026-01-19","updated":"2026-06-30","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-23534","references":[{"url":"https://github.com/FreeRDP/FreeRDP/blob/38514dfa5813aa945a86cfbcec279033f8394468/libfreerdp/codec/clear.c#L878-L879","label":"security-advisories@github.com"},{"url":"https://github.com/FreeRDP/FreeRDP/blob/38514dfa5813aa945a86cfbcec279033f8394468/libfreerdp/codec/clear.c#L883-L884","label":"security-advisories@github.com"},{"url":"https://github.com/FreeRDP/FreeRDP/releases/tag/3.21.0","label":"security-advisories@github.com"},{"url":"https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-3frr-mp8w-4599","label":"security-advisories@github.com"},{"url":"https://access.redhat.com/errata/RHSA-2026:2048","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://access.redhat.com/errata/RHSA-2026:2081","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://access.redhat.com/errata/RHSA-2026:2222","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://access.redhat.com/errata/RHSA-2026:2736","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://access.redhat.com/errata/RHSA-2026:2952","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://access.redhat.com/errata/RHSA-2026:3037","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://access.redhat.com/security/cve/CVE-2026-23534","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2430888","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-23534.json","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}],"tags":["nvd"],"epss":0.00521,"epssPercentile":0.43259,"ingestedAt":"2026-06-30T13:26:50.513Z","slug":"CVE-2026-23534","body":"## Overview\n\nFreeRDP 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.\n\n## Affected\n\n- `freerdp < 3.21.0`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `freerdp 3.21.0`","depth":"midnight","depthScore":54,"depthScoreParts":{"impact":53.9,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}