CVE-2026-33984 (GCVE-0-2026-33984)

Vulnerability from cvelistv5 – Published: 2026-03-30 21:42 – Updated: 2026-04-02 12:57
VLAI?
Title
FreeRDP: ClearCodec resize_vbar_entry() Heap OOB Write
Summary
FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to version 3.24.2, in resize_vbar_entry() in libfreerdp/codec/clear.c, vBarEntry->size is updated to vBarEntry->count before the winpr_aligned_recalloc() call. If realloc fails, size is inflated while pixels still points to the old, smaller buffer. On a subsequent call where count <= size (the inflated value), realloc is skipped. The caller then writes count * bpp bytes of attacker-controlled pixel data into the undersized buffer, causing a heap buffer overflow. This issue has been patched in version 3.24.2.
Severity ?
7.5 (High)
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H
CWE
  • CWE-122 - Heap-based Buffer Overflow
  • CWE-131 - Incorrect Calculation of Buffer Size
Assigner
References
Impacted products
Vendor Product Version
FreeRDP FreeRDP Affected: < 3.24.2
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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.
  • 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.
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