CVE-2026-55827 (GCVE-0-2026-55827)

Vulnerability from cvelistv5 – Published: 2026-07-10 19:47 – Updated: 2026-07-15 03:58
VLAI
Title
FreeRDP: Heap out-of-bounds write in RemoteFX (RFX) Cache Bitmap V3 decode
Summary
FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.27.1, FreeRDP clients launched with the non-default /cache:codec:rfx option pass desktop stride and height to RemoteFX decoding for Cache Bitmap V3 data while allocating bitmap->data only for the smaller DstWidth and DstHeight in gdi_Bitmap_Decompress, allowing a malicious RDP server to trigger a heap out-of-bounds write with attacker-controlled offset and content. This issue is fixed in version 3.27.1.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H
SSVC
Exploitation: poc Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-14 00:00 UTC
CWE
  • CWE-131 - Incorrect Calculation of Buffer Size
  • CWE-787 - Out-of-bounds Write
Assigner
References
Impacted products
Vendor Product Version CPE status
FreeRDP FreeRDP Affected: < 3.27.1
guessed Create a notification for this product.
Show details on NVD website
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Sightings

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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
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Detection rules are retrieved from Rulezet.