Medium severity6.5NVD Advisory· Published Sep 15, 2026· Updated Sep 24, 2026
CVE-2026-91953
CVE-2026-91953
Description
FreeRDP versions before 3.31.0 contain a heap buffer overflow vulnerability in nego_send_negotiation_request() that fails to validate the LB_LOAD_BALANCE_INFO field length before writing to a fixed 512-byte buffer. A malicious RDP server or man-in-the-middle can send a Server Redirection PDU with an oversized LB_LOAD_BALANCE_INFO value to overflow the buffer with attacker-controlled content, causing denial of service or heap corruption before authentication completes.
AI Insight
LLM-synthesized narrative grounded in this CVE's description and references.
Affected products
8- osv-coords6 versionspkg:rpm/almalinux/freerdppkg:rpm/almalinux/freerdp-develpkg:rpm/almalinux/freerdp-libspkg:rpm/almalinux/freerdp-serverpkg:rpm/almalinux/libwinprpkg:rpm/almalinux/libwinpr-devel
< 2:3.10.3-12.el10_2.14+ 5 more
- (no CPE)range: < 2:3.10.3-12.el10_2.14
- (no CPE)range: < 2:3.10.3-12.el10_2.14
- (no CPE)range: < 2:3.10.3-12.el10_2.14
- (no CPE)range: < 2:3.10.3-12.el10_2.14
- (no CPE)range: < 2:3.10.3-12.el10_2.14
- (no CPE)range: < 2:3.10.3-12.el10_2.14
Patches
Vulnerability mechanics
References
2- github.com/FreeRDP/FreeRDP/security/advisories/GHSA-r9pv-ffph-6gg6nvdExploitMitigationVendor Advisory
- www.vulncheck.com/advisories/freerdp-before-3.31.0-heap-buffer-overflow-via-lb-load-balance-infonvdThird Party Advisory
News mentions
1- FreeRDP: 20 Vulnerabilities Disclosed, Including Critical RDSTLS BypassVypr Intelligence · Sep 15, 2026