CVE-2026-33987: FreeRDP: Persistent Cache bmpSize Desync - Heap OOB Write

Severity: medium (CVSS 6.6 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.1% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-03-30 · updated 2026-06-17
Weakness: CWE-122

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.

Affected products

FreeRDP: before 3.24.2 — fixed in 3.24.2

How to fix

Upgrade to a fixed version: FreeRDP 3.24.2. Check the vendor advisory for mitigations.

References

https://github.com/FreeRDP/FreeRDP/commit/1a890eb43492b5eb707cb3dd6fc908f696e8fc1c
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-ff8h-p5vc-wcwc

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