{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-20242","assignerOrgId":"d1c1063e-7a18-46af-9102-31f8928bc633","state":"PUBLISHED","assignerShortName":"cisco","dateReserved":"2025-10-08T11:59:15.400Z","datePublished":"2026-09-16T20:08:27.904Z","dateUpdated":"2026-09-18T03:55:57.449Z"},"containers":{"cna":{"title":"Cisco Secure Firewall Management Center Software Java Deserialization Remote Code Execution Vulnerability","metrics":[{"format":"cvssV3_1","cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","baseScore":9.8,"baseSeverity":"CRITICAL","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"HIGH","integrityImpact":"HIGH","availabilityImpact":"HIGH"}}],"descriptions":[{"lang":"en","value":"A vulnerability in the External Database Access feature of Cisco Secure Firewall Management Center (FMC) Software could allow an unauthenticated, remote attacker to execute arbitrary commands as&nbsp;root on an affected device.\r\n\r\nThis vulnerability is due to insecure deserialization of a user-supplied Java byte stream from a host that is configured in the external database access list. An attacker could exploit this vulnerability by sending a crafted, serialized Java byte stream to a specific TCP port of an affected device. A successful exploit could allow the attacker to execute arbitrary commands on the device and elevate privileges to root.\r\nNotes:\r\n\r\nThis vulnerability can be exploited only by an attacker who has control of a host in the external database access list.\r\nIf the FMC management interface does not have public internet access, the attack surface that is associated with this vulnerability is reduced."}],"references":[{"url":"https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-fmc-javarce-y2NypXwk","name":"cisco-sa-fmc-javarce-y2NypXwk"}],"exploits":[{"lang":"en","value":"The Cisco Product Security Incident Response Team (PSIRT) is not aware of any public announcements or malicious use of the vulnerability that is described in this advisory."}],"source":{"advisory":"cisco-sa-fmc-javarce-y2NypXwk","discovery":"EXTERNAL","defects":["CSCwu16938"]},"problemTypes":[{"descriptions":[{"lang":"en","description":"Deserialization of Untrusted Data","type":"cwe","cweId":"CWE-502"}]}],"affected":[{"vendor":"Cisco","product":"Cisco Secure Firewall Management Center (FMC)","versions":[{"version":"7.0.0","status":"affected"},{"version":"7.0.0.1","status":"affected"},{"version":"7.0.1","status":"affected"},{"version":"7.0.1.1","status":"affected"},{"version":"7.0.2","status":"affected"},{"version":"7.2.0","status":"affected"},{"version":"7.0.2.1","status":"affected"},{"version":"7.0.3","status":"affected"},{"version":"7.2.0.1","status":"affected"},{"version":"7.0.4","status":"affected"},{"version":"7.2.1","status":"affected"},{"version":"7.0.5","status":"affected"},{"version":"7.3.0","status":"affected"},{"version":"7.2.2","status":"affected"},{"version":"7.3.1","status":"affected"},{"version":"7.2.3","status":"affected"},{"version":"7.2.3.1","status":"affected"},{"version":"7.2.4","status":"affected"},{"version":"7.0.6","status":"affected"},{"version":"7.2.4.1","status":"affected"},{"version":"7.2.5","status":"affected"},{"version":"7.3.1.1","status":"affected"},{"version":"7.4.0","status":"affected"},{"version":"7.0.6.1","status":"affected"},{"version":"7.2.5.1","status":"affected"},{"version":"7.4.1","status":"affected"},{"version":"7.2.6","status":"affected"},{"version":"7.4.1.1","status":"affected"},{"version":"7.0.6.2","status":"affected"},{"version":"7.2.7","status":"affected"},{"version":"7.2.5.2","status":"affected"},{"version":"7.3.1.2","status":"affected"},{"version":"7.2.8","status":"affected"},{"version":"7.6.0","status":"affected"},{"version":"7.4.2","status":"affected"},{"version":"7.2.8.1","status":"affected"},{"version":"7.0.6.3","status":"affected"},{"version":"7.4.2.1","status":"affected"},{"version":"7.2.9","status":"affected"},{"version":"7.0.7","status":"affected"},{"version":"7.7.0","status":"affected"},{"version":"7.4.2.2","status":"affected"},{"version":"7.2.10","status":"affected"},{"version":"7.6.1","status":"affected"},{"version":"7.4.2.3","status":"affected"},{"version":"7.0.8","status":"affected"},{"version":"7.6.2","status":"affected"},{"version":"7.7.10","status":"affected"},{"version":"7.2.10.1","status":"affected"},{"version":"7.0.8.1","status":"affected"},{"version":"7.6.2.1","status":"affected"},{"version":"7.2.10.2","status":"affected"},{"version":"7.7.10.1","status":"affected"},{"version":"7.4.2.4","status":"affected"},{"version":"7.4.3","status":"affected"},{"version":"7.6.3","status":"affected"},{"version":"7.7.11","status":"affected"},{"version":"7.6.4","status":"affected"},{"version":"10.0.0","status":"affected"},{"version":"7.4.4","status":"affected"},{"version":"7.4.5","status":"affected"},{"version":"7.0.9","status":"affected"},{"version":"7.2.11","status":"affected"},{"version":"7.7.12","status":"affected"},{"version":"7.6.5","status":"affected"},{"version":"7.4.6","status":"affected"},{"version":"10.0.1","status":"affected"},{"version":"7.4.7","status":"affected"}],"defaultStatus":"unknown"}],"providerMetadata":{"orgId":"d1c1063e-7a18-46af-9102-31f8928bc633","shortName":"cisco","dateUpdated":"2026-09-16T20:08:27.904Z"}},"adp":[{"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-09-17T00:00:00+00:00","options":[{"Exploitation":"none"},{"Automatable":"yes"},{"Technical Impact":"total"}],"role":"CISA Coordinator","version":"2.0.3","id":"CVE-2026-20242"}}}],"title":"CISA ADP Vulnrichment","providerMetadata":{"orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP","dateUpdated":"2026-09-18T03:55:57.449Z"}}]}}