CVE-2026-31806
What it is
FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.24.0, the gdi_surface_bits() function processes SURFACE_BITS_COMMAND messages sent by the RDP server. When the command is handled using NSCodec, the bmp.width and bmp.height values provided by the server are not properly validated against the actual desktop dimensions. A malicious RDP server can supply crafted bmp.width and bmp.height values that exceed the expected surface size. Because these values are used during bitmap decoding and memory operations without proper bounds checking, this can lead to a heap buffer overflow. Since the attacker can also control the associated pixel data transmitted by the server, the overflow may be exploitable to overwrite adjacent heap memory. This vulnerability is fixed in 3.24.0.
At a glance
- Exploitability
- Can be exploited over the network without logging in. High risk of data exposure, data tampering, service disruption.
- Exploit odds
- 0.7% chance of exploitation in the next 30 days (EPSS).
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 0.7% in the next 30 days (EPSS).
- Severity: 9.3 CRITICAL (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 0.7% · EPSS, next 30 days
- Weakness
- CWE-122
- Record status
- Modified
Affected
- Freerdp < 3.24.0
Attack profile CVSS 4.0 · 9.3
- Attack vector
- Network
- Complexity
- Low
- Attack requirements
- None
- Privileges needed
- None
- User interaction
- None
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Raw vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/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
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2026-31806.md and follow it. Check whether this project is affected by CVE-2026-31806. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
Fix and advisories
- https://github.com/FreeRDP/FreeRDP/commit/83d9aedea278a74af3e490ff5eeb889c016dbb2b
- https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-rrqm-46rj-cmx2
References
- https://github.com/FreeRDP/FreeRDP/commit/83d9aedea278a74af3e490ff5eeb889c016dbb2b
- https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-rrqm-46rj-cmx2
- https://access.redhat.com/errata/RHSA-2026:10076
- https://access.redhat.com/errata/RHSA-2026:10734
- https://access.redhat.com/errata/RHSA-2026:10735
- https://access.redhat.com/errata/RHSA-2026:10951
- https://access.redhat.com/errata/RHSA-2026:11323
- https://access.redhat.com/errata/RHSA-2026:19033
- https://access.redhat.com/errata/RHSA-2026:6340
- https://access.redhat.com/errata/RHSA-2026:6727
- https://access.redhat.com/errata/RHSA-2026:6743
- https://access.redhat.com/errata/RHSA-2026:6799
- https://access.redhat.com/errata/RHSA-2026:6918
- https://access.redhat.com/errata/RHSA-2026:6958
- https://access.redhat.com/errata/RHSA-2026:9640
- https://access.redhat.com/errata/RHSA-2026:9641
- https://access.redhat.com/security/cve/CVE-2026-31806
- https://bugzilla.redhat.com/show_bug.cgi?id=2447376
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-31806.json