Security readout for executives and security teams
Plain-English summary
CVE-2026-25941 affects FreeRDP clients. If a user connects to a malicious RDP server, that server may cause the client to disclose limited heap memory or crash. This is not a server-side RDP exposure; it depends on client use and user interaction.
Executive priority
Prioritize remediation for workstations, jump boxes, and tools that use FreeRDP to connect to external or untrusted RDP hosts. Treat as moderate urgency because exploitation requires user interaction and expected impact is limited information disclosure or client crash.
Technical view
FreeRDP 2.x before 2.11.8 and 3.x before 3.23.0 contain an out-of-bounds read in the client RDPGFX channel. A malicious RDP server can send a crafted WIRE_TO_SURFACE_2 PDU where bitmapDataLength exceeds packet data, potentially reading uninitialized heap memory or crashing the client.
Likely exposure
Exposure is limited to systems running vulnerable FreeRDP client versions, especially where users connect to untrusted or externally controlled RDP servers. FreeRDP server exposure is not described in the sources.
Exploitation context
The vulnerability is network reachable from a malicious RDP server but requires a user to connect. The provided sources do not show CISA KEV listing or active exploitation evidence.
Researcher notes
The issue maps to CWE-125 and CWE-20. The advisory identifies the affected component as the FreeRDP client RDPGFX channel and the vulnerable WIRE_TO_SURFACE_2 bitmapDataLength handling. Avoid assuming broader product impact beyond the stated FreeRDP version ranges.
Mitigation direction
- Upgrade FreeRDP 2.x to 2.11.8 or later.
- Upgrade FreeRDP 3.x to 3.23.0 or later.
- Restrict users from connecting to untrusted RDP servers.
- Check operating system or package vendor guidance for backported fixes.
Validation and detection
- Inventory installed FreeRDP versions across endpoints and images.
- Flag FreeRDP 2.x versions below 2.11.8.
- Flag FreeRDP 3.x versions below 3.23.0.
- Confirm patched package versions after updates.
- Review whether affected clients connect to untrusted RDP servers.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-125: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCWE-20: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCVE-2026-25941 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Medium
- CVSS
- 4.3 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N2.81.4Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
4.3MediumVector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N
Source materials
- CVE List V5 sourceCVE List V5
- https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-3546-x645-5cf8CVE reference · x_refsource_CONFIRM
- https://github.com/FreeRDP/FreeRDP/commit/2e3b77e28ac6a398897d28ba464dcc5dfab9c9e2CVE reference · x_refsource_MISC
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Out-of-bounds Read
Out-of-bounds Read represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.
Improper Input Validation
Improper Input Validation represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.