CVE-2026-67300 (GCVE-0-2026-67300)

Vulnerability from cvelistv5 – Published: 2026-08-01 12:22 – Updated: 2026-08-03 15:37
VLAI
Title
FreeRDP before 3.29.0 Use-After-Free via async message proxy
Summary
FreeRDP before 3.29.0 contains client-side heap use-after-free vulnerabilities in the async update message proxy for RAIL WINDOW_STATE_ORDER and NOTIFY_ICON_STATE_ORDER when AsyncUpdate is enabled. When a malicious or compromised RDP server sends crafted update orders, the message proxy shallow-copies structures containing nested parser-owned pointers (e.g., titleInfo.string, windowRects, visibilityRects, icon buffers). The parser frees those nested buffers after the callback returns, so the queued async message later dispatches stale pointers, potentially causing memory corruption or a client crash.
Severity
8.7 (High)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-03 15:00 UTC
CWE
Assigner
References
Impacted products
Vendor Product Version CPE status
FreeRDP FreeRDP Affected: 0 , < 3.29.0 (semver)
Unaffected: 3.29.0 (semver)
    cpe:2.3:a:freerdp:freerdp:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-07-15 00:00
Show details on NVD website
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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • 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.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.