Buffer overflow in Freerdp

CVE-2026-33984

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.

Vulnerability class: Buffer Overflow

EPSS: 0.004 (32.5th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-33984?
CVE-2026-33984 is a high-severity vulnerability in Freerdp, classified under Heap-based Buffer Overflow. CVSS score: 7.5/10. Published 2026-03-30.
How severe is CVE-2026-33984?
High severity. CVSS v3 base score is 7.5 out of 10.