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{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[0,1.4.5-0684)"}}], "enrichment": {"confidence": 84.0, "confidence_source": "matching", "scores": [{"score": 84.0, "source": "matching"}]}, "original": {"product": "Synology SSL VPN Client", "source": "cna", "vendor": "Synology"}, "product": "ssl_vpn_client", "vendor": "synology"}], "analysis": {"en": {"generated_at": "2026-04-10T10:50:27.481546+00:00", "value": {"mitigation_remediation": ["Upgrade Synology SSL VPN Client to version 1.4.5\u20110684 or later"], "summary": {"action": "Patch Immediately", "impact": "Unauthorized VPN configuration and potential traffic interception"}, "threat_synthesis": {"affected_systems": "Synology SSL VPN Client, all releases earlier than 1.4.5\u20110684.", "description_and_impact": "An insecure storage mechanism in Synology SSL VPN Client versions before 1.4.5\u20110684 records the user\u2019s PIN in plain text. This weakness allows an attacker to read or modify the PIN, which can in turn enable unauthorized configuration of the VPN or compromise the integrity of subsequent VPN traffic. The flaw is a password storage vulnerability, identified as CWE\u2011256.", "risk_and_exploitability": "The CVSS score of 8.1 signals high severity. No EPSS data or KEV listing indicates that widespread exploitation has not yet been observed, although the vulnerability remains theoretically exploitable. Achieving the attack likely requires the attacker to gain access to the client on the user\u2019s machine, such as through malicious software or local privilege escalation, to read or alter the stored PIN. Once the PIN is compromised, an attacker can configure the VPN or trick the user into accepting changes, which may allow interception or tampering of VPN traffic."}}}}, "created": "2026-04-13T12:44:57.808915+00:00", "title": "Plaintext Password Storage in Synology SSL VPN Client Enabling Unauthorized VPN Configuration", "updated": "2026-04-13T13:06:11.086868+00:00", "vendors": ["synology", "synology$PRODUCT$ssl_vpn_client"]}