CVE-2026-44421 (GCVE-0-2026-44421)
Vulnerability from cvelistv5 – Published: 2026-05-29 19:40 – Updated: 2026-07-27 12:05
VLAI
EPSS
VEX
Title
FreeRDP RDPGFX CacheToSurface heap-buffer-overflow via clamped-rectangle validation bypass
Summary
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.
Severity
8.8 (High)
SSVC
Exploitation: poc
Automatable: no
Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-06-01 00:00 UTC
Assigner
GitHub_M
CNA
References
6 references
| URL | Tags |
|---|---|
| https://github.com/FreeRDP/FreeRDP/security/advis… | x_refsource_CONFIRM |
| https://access.redhat.com/security/cve/CVE-2026-44421 | vdb-entryx_refsource_REDHAT |
| https://bugzilla.redhat.com/show_bug.cgi?id=2483471 | issue-trackingx_refsource_REDHAT |
| https://security.access.redhat.com/data/csaf/v2/v… | x_sadp-csaf-vex |
| https://access.redhat.com/errata/RHSA-2026:46393 | vendor-advisoryx_refsource_REDHAT |
| https://access.redhat.com/errata/RHSA-2026:36203 | vendor-advisoryx_refsource_REDHAT |
Impacted products
6 products
| Vendor | Product | Version | |
|---|---|---|---|
| FreeRDP | FreeRDP |
Affected:
< 3.26.0
|
|
| Red Hat | Red Hat Enterprise Linux 10 |
Unaffected:
2:3.10.3-12.el10_2.6 , < *
(rpm)
cpe:/o:redhat:enterprise_linux:10.2 |
|
| Red Hat | Red Hat Enterprise Linux 6 |
cpe:/o:redhat:enterprise_linux:6
|
|
| Red Hat | Red Hat Enterprise Linux 7 |
cpe:/o:redhat:enterprise_linux:7
|
|
| Red Hat | Red Hat Enterprise Linux 8 |
cpe:/o:redhat:enterprise_linux:8
|
|
| Red Hat | Red Hat Enterprise Linux 9 |
cpe:/o:redhat:enterprise_linux:9
|
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