Buffer overflow in Freerdp
CVE-2026-121952
FreeRDP before 3.32.2 has an out-of-bounds write in the proxy because rdp_read_bitmap_cache_v2_capability_set rejects only numCellCaches values above 5, yet the bitmap cache v2 cell array is later accessed at fixed indices 0 through 4. A client connecting to the proxy can declare fewer than five cell caches in its Confirm Active, causing heap corruption, heap data leakage to the backend, or a crash.
Vulnerability class: Buffer Overflow
Published · last modified .
CVSS v3 metric
CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
Weakness classification (CWE)
References
- github.com/FreeRDP/FreeRDP/security/advisories/GHSA-xc85-4mqc-xgcx (Exploit, vendor-advisory, Mitigation, Vendor Advisory)
- www.vulncheck.com/advisories/freerdp-before-3.32.2-proxy-out-of-bounds-write-vi… (Third Party Advisory, third-party-advisory)
Frequently asked questions
- What is CVE-2026-121952?
- CVE-2026-121952 is a critical-severity vulnerability in Freerdp, classified under Out-of-bounds Write. CVSS score: 9.8/10. Published 2026-11-04.
- How severe is CVE-2026-121952?
- Critical severity. CVSS v3 base score is 9.8 out of 10.