CVE-2026-33984 PUBLISHED

FreeRDP: ClearCodec resize_vbar_entry() Heap OOB Write

Assigner: GitHub_M
Reserved: 24.03.2026 Published: 30.03.2026 Updated: 30.03.2026

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.

Metrics

CVSS Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H
CVSS Score: 7.5

Product Status

Vendor FreeRDP
Product FreeRDP
Versions
  • Version < 3.24.2 is affected

References

Problem Types

  • CWE-122: Heap-based Buffer Overflow CWE
  • CWE-131: Incorrect Calculation of Buffer Size CWE