CVE-2026-33984 — FreeRDP: ClearCodec resize_vbar_entry() Heap OOB Write

Description (CNA)

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.

Affected (CNA)

Vendor / product	Versions
FreeRDP / FreeRDP	affected < 3.24.2

CWE

CWE-122, CWE-131

References

ADP enrichment

CISA-ADP

No English description supplied.

No references supplied.

redhat-SADP

A flaw was found in FreeRDP, a free implementation of the Remote Desktop Protocol. A remote attacker could exploit a heap buffer overflow vulnerability in the `resize_vbar_entry()` function. This occurs when an error in buffer resizing leads to attacker-controlled pixel data being written into an undersized memory buffer. Successful exploitation could result in arbitrary code execution.