{"id":"CVE-2026-55191","aliases":[],"url":"https://o3.security/vulnerability/CVE-2026-55191","summary":"FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.27.0, FreeRDP clients that negotiate RDPGFX AVC444 with an H.264 decoder backend calculate the intermediate…","details":"FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.27.0, FreeRDP clients that negotiate RDPGFX AVC444 with an H.264 decoder backend calculate the intermediate YUV444 allocation size in libfreerdp/codec/h264.c with 32-bit multiplication in avc444_ensure_buffer. A malicious RDP server can supply surface dimensions for which piDstStride multiplied by padDstHeight wraps to a small nonzero value, causing winpr_aligned_recalloc to allocate an undersized buffer before YUV420CombineToYUV444 writes using the actual stride and rectangle dimensions. This can cause a client crash and may permit code execution through attacker-influenced heap corruption. This issue is fixed in version 3.27.0.","published":"2026-08-19T18:16:44.427","modified":"2026-08-19T18:16:44.427","cvss":null,"epss":null,"cisaKev":null,"exploitsKnown":null,"affectedPackages":[],"fix":{"url":"https://github.com/FreeRDP/FreeRDP/commit/97f40b9e766af375f4e41ac6a3f4397d708d249c","label":"FreeRDP/FreeRDP@97f40b9"},"references":[{"type":"WEB","url":"https://github.com/FreeRDP/FreeRDP/commit/97f40b9e766af375f4e41ac6a3f4397d708d249c"},{"type":"WEB","url":"https://github.com/FreeRDP/FreeRDP/pull/12873"},{"type":"WEB","url":"https://github.com/FreeRDP/FreeRDP/releases/tag/3.27.0"},{"type":"WEB","url":"https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-vx73-w5q6-7jqr"}],"provenance":{"sources":["OSV.dev","NVD","FIRST.org (EPSS)"],"lastVerified":"2026-08-19T18:16:44.427"}}