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CVE-2026-23732 (GCVE-0-2026-23732)

Vulnerability from cvelistv5 – Published: 2026-01-19 17:12 – Updated: 2026-01-20 15:34
VLAI
Title
FreeRDP has heap-buffer-overflow in Glyph_Alloc
Summary
FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to version 3.21.0, FastGlyph parsing trusts `cbData`/remaining length and never validates against the minimum size implied by `cx/cy`. A malicious server can trigger a client‑side global buffer overflow, causing a crash (DoS). Version 3.21.0 contains a patch for the issue.
Severity
5.5 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P
SSVC
Exploitation: poc Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-01-20 15:34 UTC
CWE
  • CWE-122 - Heap-based Buffer Overflow
Assigner
References
Impacted products
Vendor Product Version CPE status
FreeRDP FreeRDP Affected: < 3.21.0
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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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.


Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.