Description
FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.26.0, a malicious RDP server can trigger a heap-buffer-overflow write in the FreeRDP client by sending crafted RDPGFX PDUs. The bug is in gdi_CacheToSurface: it validates a destination rectangle that is clamped to UINT16_MAX, but then performs the copy using the original cacheEntry->width/height. This can cause a large out-of-bounds heap write and may lead to client crashes or code execution. This bug is reachable from a malicious RDP server, but only when the client has RDPGFX enabled. This vulnerability is fixed in 3.26.0.
Affected products
freerdp: freerdp
References7
- github.com/FreeRDP/FreeRDP/security/advisories/GHSA-p6r2-4hgm-m… ExploitMitigationVendor Advisory
- github.com/FreeRDP/FreeRDP/security/advisories/GHSA-p6r2-4hgm-m… ExploitMitigationVendor Advisory
- access.redhat.com/errata/RHSA-2026:36203
- access.redhat.com/errata/RHSA-2026:46393
- access.redhat.com/security/cve/CVE-2026-44421
- bugzilla.redhat.com/show_bug.cgi?id=2483471
- security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-44421…
Metrics
- CVSS 3.1
-
8.8
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 1% percentile: 44 · as of 15 November 2026
- CWE
- CWE-122CWE-787
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