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{"bugzilla": {"description": "FreeRDP: FreeRDP: Heap buffer overflow via oversized LB_LOAD_BALANCE_INFO routing token can lead to heap corruption.", "id": "2533959", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2533959"}, "csaw": false, "cvss3": {"cvss3_base_score": "6.5", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H", "status": "draft"}, "cwe": "CWE-120", "details": ["A flaw was found in FreeRDP. A malicious RDP (Remote Desktop Protocol) server or a man-in-the-middle attacker could exploit a heap buffer overflow vulnerability during connection negotiation, prior to authentication. By sending a specially crafted Server Redirection PDU (Protocol Data Unit) with an oversized LB_LOAD_BALANCE_INFO field, an attacker could cause a denial of service or heap corruption on the client system."], "mitigation": {"lang": "en:us", "value": "To prevent exploitation of this heap buffer overflow, FreeRDP clients should only be used to connect to trusted RDP servers. This operational control reduces the risk of encountering a malicious server redirection PDU."}, "name": "CVE-2026-91953", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Affected", "package_name": "freerdp", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Out of support scope", "package_name": "freerdp", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Affected", "package_name": "freerdp", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Affected", "package_name": "freerdp", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Affected", "package_name": "freerdp", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2026-09-15T15:18:09Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-91953\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-91953\nhttps://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-r9pv-ffph-6gg6\nhttps://www.vulncheck.com/advisories/freerdp-before-3.31.0-heap-buffer-overflow-via-lb-load-balance-info"], "threat_severity": "Moderate"}

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