CVE-2026-27445

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{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[0,15.0.1)"}}], "enrichment": {"confidence": 87.0, "confidence_source": "matching", "scores": [{"score": 95.0, "source": "inferred"}, {"score": 87.0, "source": "matching"}]}, "original": {"product": "Secure Email Gateway", "source": "cna", "vendor": "SEPPmail"}, "product": "seppmail_secure_email_gateway", "vendor": "seppmail"}], "analysis": {"en": {"generated_at": "2026-04-17T13:13:04.513546+00:00", "value": {"mitigation_remediation": ["Upgrade SEPPmail Secure Email Gateway to version 15.0.1 or later, which includes proper PGP signature verification.", "If an immediate upgrade is not feasible, temporarily disable automatic PGP signature verification on the gateway and manually verify signatures using an independent PGP tool until a patch is applied.", "Implement monitoring to flag emails that are purportedly signed by trusted keys but fail local verification, and establish a quarantine process for suspicious messages."], "summary": {"action": "Apply patch", "impact": "Signature spoofing causing undetected forged signatures"}, "threat_synthesis": {"affected_systems": "The vulnerability affects SEPPmail Secure Email Gateway deployments running any version prior to 15.0.1, including all releases labeled simply \"SEPPmail\" and those marketed as the Secure Email Gateway component. No later versions are affected.", "description_and_impact": "SEPPmail Secure Email Gateway fails to verify that a PGP signature was generated by the expected key. An attacker can craft a message with a forged signature that will be accepted by the system, making the message appear authentic. This undermines the integrity and authenticity guarantees of email communications and can be leveraged for phishing, man\u2011in\u2011the\u2011middle attacks, or other social\u2011engineering tactics. The weakness is a failure to enforce proper cryptographic signature validation, identified as CWE-347.", "risk_and_exploitability": "The CVSS score of 6.9 indicates moderate severity; combined with an EPSS score of less than 1\u202f% the likelihood of widespread exploitation is low. The vulnerability has not been listed in CISA\u2019s KEV catalog, suggesting no known large\u2011scale exploitation yet. Exploitation appears possible remotely by sending a crafted PGP\u2011signed email to the vulnerable gateway; no local privileges or additional access are required beyond normal email submission rights. The attack vector is therefore likely network\u2011based via the email ingestion interface."}}}}, "created": "2026-03-04T21:03:48.311583+00:00", "updated": "2026-04-17T13:15:19.691307+00:00", "vendors": ["seppmail", "seppmail$PRODUCT$seppmail_secure_email_gateway"]}