CVE-2026-33987 FreeRDP: Persistent Cache bmpSize Desync - Heap OOB Write
A heap out-of-bounds write in FreeRDP's persistent cache allows attackers to execute arbitrary code or cause denial of service.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2026-33987?
CVE-2026-33987 is a high-severity memory corruption vulnerability in Freerdp Freerdp, published on 30 Mar 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.
Official description
FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to version 3.24.2, in persistent_cache_read_entry_v3() in libfreerdp/cache/persistent.c, persistent->bmpSize is updated before winpr_aligned_recalloc(). If realloc fails, bmpSize is inflated while bmpData points to the old buffer. This issue has been patched in version 3.24.2.
Which versions are affected by CVE-2026-33987?
It affects 1 product.
Products include Freerdp Freerdp.
How do I fix CVE-2026-33987?
Upgrade to a fixed version.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2026-33987 being exploited?
There is no known exploitation of CVE-2026-33987 in the wild and no public exploit code.
Other vulnerabilities in Freerdp Freerdp
- CVE-2021-37594 Other in n/a
- CVE-2021-37595 Other in n/a
- CVE-2026-67305 FreeRDP Windows Client before 3.29.0 Heap Buffer Overflow via Cliprdr
- CVE-2026-66402 FreeRDP before 3.29.0 TLS Certificate Identity Validation Bypass
- CVE-2026-67289 FreeRDP before 3.29.0 HTTP Proxy Request Injection via Redirection
Sources
Also known as DEBIAN-CVE-2026-33987, GHSA-ff8h-p5vc-wcwc, UBUNTU-CVE-2026-33987.