VDB
CVE-2026-55564
CVE-2026-55564
PUBLISHED
CVSS 5.4 MEDIUM
Reported by GitHub_M · Published August 19, 2026
FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.27.0, the glyph_cache_get function in libfreerdp/cache/glyph.c checks whether index is greater than cache->number instead of greater than or equal to it. A malicious RDP server can use GLYPH_FRAGMENT_USE replay in update_process_glyph_fragments to make the default cache receive index 254 when cache->number is 254, reading one pointer beyond the entries array and dereferencing it as a glyph. This can crash the client and may disclose adjacent heap data. This issue is fixed in version 3.27.0.
Risk Scores
CVSS 3.1
5.4
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:L
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| FreeRDP | FreeRDP | < 3.27.0 |
| FreeRDP | FreeRDP | < 3.27.0, < 3.27.0 |
Timeline
- Aug 19, 2026 CVE Published
- Aug 22, 2026 Coalition ESS Score
- Aug 24, 2026 EPSS Score
- Aug 28, 2026 EPSS Score
- Sep 4, 2026 Security Advisory
- Sep 5, 2026 EPSS Score
- Sep 9, 2026 EPSS Score
- Sep 9, 2026 CVE Updated
- Sep 10, 2026 EPSS Score
- Sep 12, 2026 EPSS Score
- Sep 16, 2026 EPSS Score
- Sep 18, 2026 EPSS Score
References
- https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-6xmj-pr98-cx4c x_refsource_CONFIRM
- https://github.com/FreeRDP/FreeRDP/pull/12885 x_refsource_MISC
- https://github.com/FreeRDP/FreeRDP/commit/c29324750e3cbcba8761f147b7a5235cc686930f x_refsource_MISC
- https://github.com/FreeRDP/FreeRDP/releases/tag/3.27.0 x_refsource_MISC