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{"bugzilla": {"description": "freerdp: FreeRDP: Heap buffer overflow leads to denial of service and potential code execution", "id": "2430886", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2430886"}, "csaw": false, "cvss3": {"cvss3_base_score": "7.6", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:H", "status": "draft"}, "cwe": "CWE-122", "details": ["A flaw was found in FreeRDP, a free implementation of the Remote Desktop Protocol. A malicious server can exploit a client-side heap buffer overflow vulnerability in the RDPGFX ClearCodec decode path. This occurs when maliciously crafted residual data causes out-of-bounds writes during color output. Successful exploitation can lead to a crash, resulting in a Denial of Service (DoS), and potentially heap corruption with a risk of arbitrary code execution."], "name": "CVE-2026-23533", "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": "Affected", "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": "2026-01-19T17:07:18Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-23533\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-23533\nhttps://github.com/FreeRDP/FreeRDP/blob/38514dfa5813aa945a86cfbcec279033f8394468/libfreerdp/codec/clear.c#L268-L281\nhttps://github.com/FreeRDP/FreeRDP/blob/38514dfa5813aa945a86cfbcec279033f8394468/libfreerdp/codec/clear.c#L336\nhttps://github.com/FreeRDP/FreeRDP/releases/tag/3.21.0\nhttps://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-32q9-m5qr-9j2v"], "statement": "For this vulnerability to be exploited, a client must connect to a maliciously-configured server. Red Hat recommends that FreeRDP clients are only used to connect to trusted servers.", "threat_severity": "Important"}

{"analysis": {"en": {"generated_at": "2026-04-18T05:09:50.779687+00:00", "value": {"mitigation_remediation": ["Upgrade FreeRDP to version 3.21.0 or later, which contains the fix for the ClearCodec overflow.", "If an immediate upgrade is not possible, limit client exposure by connecting only to trusted servers or by blocking unsolicited RDP traffic from untrusted networks.", "Apply network segmentation or firewall rules to restrict inbound RDP connections to known, authorized hosts, reducing the attack surface while a patch is deployed."], "summary": {"action": "Immediate Patch", "impact": "Client\u2011side heap buffer overflow leading to denial of service and potential code execution"}, "threat_synthesis": {"affected_systems": "This vulnerability affects all FreeRDP clients released prior to version 3.21.0. Any system running a legacy FreeRDP client within a remote desktop session is potentially exposed.", "description_and_impact": "FreeRDP, a free Remote Desktop Protocol implementation, has a heap\u2011buffer overflow in the ClearCodec decode path. A malicious RDP server can send specially crafted residual data that triggers out\u2011of\u2011bounds writes on the client\u2019s heap. The overflow can cause the client to crash, producing a denial\u2011of\u2011service, and may corrupt heap metadata, creating an opportunity for an attacker to execute arbitrary code depending on the memory allocator and surrounding layout.", "risk_and_exploitability": "The CVSS score of 7.7 indicates a moderate\u2011high severity, while the EPSS score of less than 1% suggests a currently low exploitation probability. The vulnerability is not listed in CISA\u2019s KEV catalog. The attack vector is remote; an attacker controls the RDP server and can send malicious packets to affect the client. The impact includes crash, denial of service, heap corruption, and potential remote code execution if heap exploitation succeeds."}}}}, "created": "2026-01-20T08:40:54.477545+00:00", "updated": "2026-04-18T05:15:15.980590+00:00", "vendors": ["freerdp", "freerdp$PRODUCT$freerdp"]}