Answer in brief
CVE-2026-31806 records a Critical severity (CVSS 9.8) vulnerability in FreeRDP has a Heap Buffer Overflow in nsc_process_message() via Unchecked SURFACE_BITS_COMMAND Bitmap Dimensions. The current sources do not mark it as known exploited. The current feed maps FreeRDP/FreeRDP (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
Answer in brief
CVE-2026-31806 records a Critical severity (CVSS 9.8) vulnerability in FreeRDP has a Heap Buffer Overflow in nsc_process_message() via Unchecked SURFACE_BITS_COMMAND Bitmap Dimensions. The current sources do not mark it as known exploited. The current feed maps FreeRDP/FreeRDP (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 9.8. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps FreeRDP/FreeRDP (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| FreeRDP/FreeRDPgeneric | < 3.24.0 | Not reported |
Published upstream
Mar 13, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Jul 15, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Jul 15, 2026
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.
Quoted source text, attributed separately from HOL analysis.
CVSS is 9.8. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps FreeRDP/FreeRDP (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| FreeRDP/FreeRDPgeneric | < 3.24.0 | Not reported |
Published upstream
Mar 13, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Jul 15, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Jul 15, 2026
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.
Quoted source text, attributed separately from HOL analysis.