Description
FreeRDP before 3.29.0 (affected versions <= 3.28.0) contains a heap out-of-bounds read in update_process_glyph_fragments()/glyph_cache_fragment_put() in libfreerdp/cache/glyph.c. When handling a GLYPH_FRAGMENT_ADD update, the code reads a one-byte server-controlled declared fragment size but does not verify it fits within the remaining received buffer before allocating and copying that many bytes. A malicious RDP server can send a short fragment with an oversized declared size, causing the client to read beyond the allocated buffer, resulting in an out-of-bounds read and client crash.
Affected products
freerdp: freerdp
References4
- github.com/FreeRDP/FreeRDP/security/advisories/GHSA-hgj8-g595-w… ExploitVendor Advisory
- github.com/FreeRDP/FreeRDP/security/advisories/GHSA-hgj8-g595-w… ExploitVendor Advisory
- github.com/FreeRDP/FreeRDP/commit/f3b4347105114fe7453828736bea0… Patch
- www.vulncheck.com/advisories/freerdp-before-heap-out-of-bounds-… PatchThird Party Advisory
Metrics
- CVSS 3.1
-
7.5
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - CVSS 4.0
-
8.7
HIGH
Score source: CNA
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - EPSS — exploit probability
- 0% percentile: 36 · as of 13 November 2026
- CWE
- CWE-125
Could this be exploited in your environment?
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