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OpenAdvisories
Medium · 5.4 CVE-2026-55564 EUVD-2026-62662

FreeRDP: Out-of-bounds read in glyph_cache_get via crafted glyph fragments

Published Aug 19, 2026 · Updated Aug 25, 2026 · Assigned by GitHub_M

Description

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 products

VendorProductAffectedFixed
FreeRDP FreeRDP < 3.27.0 —

Fixed in Linux distributions

Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.

ReleasePackageFixed inAdvisory
Debian 14 freerdp3 3.27.0+dfsg-1 —
Debian 13 freerdp3 No fix yet —
Debian 12 freerdp2 No fix yet —
ReleasePackageFixed inAdvisory
Ubuntu 26.04 LTS freerdp3 3.30.0+dfsg-0ubuntu0.26.04.1 USN-8561-1
Ubuntu 25.10 freerdp3 No fix yet —
Ubuntu 24.04 LTS freerdp3 3.30.0+dfsg-0ubuntu0.24.04.1 USN-8561-1
Ubuntu 22.04 LTS freerdp2 No fix yet —
Ubuntu 18.04 LTS freerdp No fix yet —
Show 4 more (older releases, extended support, other products)
ReleasePackageFixed inAdvisory
Ubuntu 16.04 LTS freerdp No fix yet —
Ubuntu Pro 24.04 LTS freerdp2 No fix yet —
Ubuntu Pro 20.04 LTS freerdp2 No fix yet —
Ubuntu Pro 18.04 LTS freerdp2 No fix yet —

Amazon Linux

ReleasePackageFixed inAdvisory
Amazon Linux 2023 freerdp +5 2:3.6.3-1.amzn2023.0.13 ALAS2023-2026-2012
Amazon Linux 2 freerdp +4 2:2.11.7-1.amzn2.0.13 ALAS2-2026-3840

Advisories 4

References