CVE-2026-55564 (GCVE-0-2026-55564)
Vulnerability from cvelistv5
Published
2026-08-19 17:45
Modified
2026-08-25 03:33
Severity ?
5.4 (Medium) - CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:L
CWE
Summary
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.
References
Impacted products
Vendor Product Version
FreeRDP FreeRDP Version: < 3.27.0
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