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{"bugzilla": {"description": "freerdp: FreeRDP global-buffer-overflow", "id": "2429649", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2429649"}, "csaw": false, "cvss3": {"cvss3_base_score": "5.9", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:N/A:L", "status": "draft"}, "cwe": "(CWE-125|CWE-758)", "details": ["No description is available for this CVE."], "mitigation": {"lang": "en:us", "value": "Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability."}, "name": "CVE-2026-22858", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Fix deferred", "package_name": "freerdp", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Fix deferred", "package_name": "freerdp", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Fix deferred", "package_name": "freerdp", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Fix deferred", "package_name": "freerdp", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Fix deferred", "package_name": "freerdp", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2026-01-14T17:56:29Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-22858\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-22858\nhttps://github.com/FreeRDP/FreeRDP/releases/tag/3.20.1\nhttps://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-qmqf-m84q-x896"], "threat_severity": "Moderate"}

{"analysis": {"en": {"generated_at": "2026-04-18T06:17:29.453759+00:00", "value": {"mitigation_remediation": ["Upgrade FreeRDP to version 3.20.1 or later", "Recompile or configure Victim builds to treat plain char as signed on Arm/AArch64 when possible", "Monitor RDP connections for abnormal Base64 traffic patterns that could indicate exploitation attempts"], "summary": {"action": "Patch Now", "impact": "Out-of-bounds memory access in Base64 decoding"}, "threat_synthesis": {"affected_systems": "The vulnerability affects FreeRDP releases older than 3.20.1, running on architectures such as Arm and AArch64 where char is unsigned. Users of FreeRDP prior to the 3.20.1 release are exposed regardless of operating system.", "description_and_impact": "FreeRDP contains a global buffer overflow in its Base64 decoding routine because signedness of plain char is implementation-defined. Non\u2011ASCII values may bypass a range check and index a global table out of bounds, corrupting memory. An attacker could exploit this to crash or potentially hijack execution on affected systems.", "risk_and_exploitability": "The CVSS score is 5.6, indicating a moderate severity. EPSS is below 1\u202f%, so widespread exploitation is unlikely at present, and the issue is not listed in CISA\u2019s KEV catalog. The likely attack vector is remote, through an RDP session that processes Base64-encoded data, such as credentials or other parameters."}}}}, "created": "2026-01-15T08:03:21.936158+00:00", "updated": "2026-04-18T06:30:25.900994+00:00", "vendors": ["freerdp", "freerdp$PRODUCT$freerdp"]}