CVE-2026-55564

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.

Affected Software

VendorProductVersion RangeStatus
FreeRDPFreeRDP< 3.27.0affected

Weaknesses

  • CWE-125: CWE-125: Out-of-bounds Read
  • CWE-193: CWE-193: Off-by-one Error

References