{"id":"CVE-2026-20131","aliases":["EUVD-2026-9444","GHSA-r229-mj76-g2qx"],"status":"published","title":"Cisco Secure Firewall Management Center Software Remote Code Execution Vulnerability","description":"A vulnerability in the web-based management interface of Cisco Secure Firewall Management Center (FMC) Software could allow an unauthenticated, remote attacker to execute arbitrary Java code as root\u0026nbsp;on an affected device.\r\n\r\nThis vulnerability is due to insecure deserialization of a user-supplied Java byte stream. An attacker could exploit this vulnerability by sending a crafted serialized Java object to the web-based management interface of an affected device. A successful exploit could allow the attacker to execute arbitrary code on the device and elevate privileges to root.\r\nNote: If the FMC management interface does not have public internet access, the attack surface that is associated with this vulnerability is reduced.","severity":{"version":"3.1","score":10,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H","level":"critical","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-10","score":0.44431,"percentile":0.98774,"model":"v2026.06.15"},"facts":{"in_kev":true,"known_exploited":true,"public_exploit":true,"fix_available":false},"cwes":["CWE-502"],"published":"2026-03-04T17:17:56Z","modified":"2026-08-14T03:55:24Z","kev":{"date_added":"2026-03-19","due_date":"2026-03-22","required_action":"Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.","known_ransomware_use":"Known"},"exploitation":[{"source":"euvd","since":"2026-03-19"},{"source":"kev","since":"2026-03-19"}],"exploits":[{"source":"pocgithub","id":"p3Nt3st3r-sTAr/CVE-2026-20131-POC","title":"p3Nt3st3r-sTAr/CVE-2026-20131-POC","date":"2026-03-06","url":"https://github.com/p3Nt3st3r-sTAr/CVE-2026-20131-POC"},{"source":"pocgithub","id":"sak110/CVE-2026-20131","title":"sak110/CVE-2026-20131","date":"2026-03-11","url":"https://github.com/sak110/CVE-2026-20131"},{"source":"pocgithub","id":"Hassan-Pouladi/Cisco-FMC-honeypot","title":"Hassan-Pouladi/Cisco-FMC-honeypot","date":"2026-04-07","url":"https://github.com/Hassan-Pouladi/Cisco-FMC-honeypot"},{"source":"pocgithub","id":"ashrafzaryouh/CVE-2026-20131","title":"ashrafzaryouh/CVE-2026-20131","date":"2026-05-10","url":"https://github.com/ashrafzaryouh/CVE-2026-20131"},{"source":"pocgithub","id":"Jwa7470/CVE-2026-20131-Post-Incident-Written-Report","title":"Jwa7470/CVE-2026-20131-Post-Incident-Written-Report","date":"2026-08-28","url":"https://github.com/Jwa7470/CVE-2026-20131-Post-Incident-Written-Report"},{"source":"pocgithub","id":"basesixtythree/B63-POC-CVE-2026-20131","title":"basesixtythree/B63-POC-CVE-2026-20131","date":"2026-10-26","url":"https://github.com/basesixtythree/B63-POC-CVE-2026-20131"}],"products":[{"vendor":"cisco","product":"cisco secure firewall management center (fmc)"},{"vendor":"cisco","product":"secure firewall management center (fmc)"},{"vendor":"cisco","product":"secure_firewall_management_center"}],"references":[{"url":"https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-fmc-rce-NKhnULJh","tags":["Vendor Advisory"]},{"url":"https://aws.amazon.com/blogs/security/amazon-threat-intelligence-teams-identify-interlock-ransomware-campaign-targeting-enterprise-firewalls/","tags":["third-party-advisory","Technical Description"]},{"url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-20131","tags":["government-resource","US Government Resource"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-20131"},{"url":"https://aws.amazon.com/blogs/security/amazon-threat-intelligence-teams-identify-interlock-ransomware-campaign-targeting-enterprise-firewalls"},{"url":"https://github.com/advisories/GHSA-r229-mj76-g2qx"}],"sources":{"cve":[{"id":"CVE-2026-20131","title":"Cisco Secure Firewall Management Center Software Remote Code Execution Vulnerability","description":"A vulnerability in the web-based management interface of Cisco Secure Firewall Management Center (FMC) Software could allow an unauthenticated, remote attacker to execute arbitrary Java code as root\u0026nbsp;on an affected device.\r\n\r\nThis vulnerability is due to insecure deserialization of a user-supplied Java byte stream. An attacker could exploit this vulnerability by sending a crafted serialized Java object to the web-based management interface of an affected device. A successful exploit could allow the attacker to execute arbitrary code on the device and elevate privileges to root.\r\nNote: If the FMC management interface does not have public internet access, the attack surface that is associated with this vulnerability is reduced.","status":"published","published":"2026-03-04T17:17:56.008Z","modified":"2026-08-14T03:55:24.856Z","cvss":[{"version":"3.1","score":10,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H","level":"critical","assessor":"cna"}],"cwes":["CWE-502"],"updated_at":"2026-11-02T13:35:44.571002Z"}],"euvd":[{"id":"EUVD-2026-9444","description":"A vulnerability in the web-based management interface of Cisco Secure Firewall Management Center (FMC) Software could allow an unauthenticated, remote attacker to execute arbitrary Java code as root\u0026nbsp;on an affected device.\r\n\r\nThis vulnerability is due to insecure deserialization of a user-supplied Java byte stream. An attacker could exploit this vulnerability by sending a crafted serialized Java object to the web-based management interface of an affected device. A successful exploit could allow the attacker to execute arbitrary code on the device and elevate privileges to root.\r\nNote: If the FMC management interface does not have public internet access, the attack surface that is associated with this vulnerability is reduced.","status":"published","published":"2026-03-04T17:17:56Z","modified":"2026-08-14T03:55:24Z","cvss":[{"version":"3.1","score":10,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H","level":"critical"}],"exploited_since":"2026-03-19","updated_at":"2026-11-02T18:01:55.248337Z"}],"ghsa":[{"id":"GHSA-r229-mj76-g2qx","title":"A vulnerability in the web-based management interface of Cisco Secure Firewall Management Center ...","description":"A vulnerability in the web-based management interface of Cisco Secure Firewall Management Center (FMC) Software could allow an unauthenticated, remote attacker to execute arbitrary Java code as root on an affected device.\n\n This vulnerability is due to insecure deserialization of a user-supplied Java byte stream. An attacker could exploit this vulnerability by sending a crafted serialized Java object to the web-based management interface of an affected device. A successful exploit could allow the attacker to execute arbitrary code on the device and elevate privileges to root.\n\n Note: If the FMC management interface does not have public internet access, the attack surface that is associated with this vulnerability is reduced.","status":"published","published":"2026-03-04T18:31:56Z","modified":"2026-03-19T18:32:21Z","cvss":[{"version":"3.1","score":10,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H","level":"critical"}],"cwes":["CWE-502"],"updated_at":"2026-11-02T15:06:43.427844Z"}],"kev":[{"id":"CVE-2026-20131","title":"Cisco Secure Firewall Management Center (FMC) Software and Cisco Security Cloud Control (SCC) Firewall Management Deserialization of Untrusted Data Vulnerability","description":"Cisco Secure Firewall Management Center (FMC) Software and Cisco Security Cloud Control (SCC) Firewall Management contain a deserialization of untrusted data vulnerability in the web-based management interface that could allow an unauthenticated, remote attacker to execute arbitrary Java code as root on an affected device.","cwes":["CWE-502"],"kev":{"date_added":"2026-03-19","due_date":"2026-03-22","required_action":"Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.","known_ransomware_use":"Known"},"updated_at":"2026-11-02T17:00:15.999436Z"}],"nvd":[{"id":"CVE-2026-20131","description":"A vulnerability in the web-based management interface of Cisco Secure Firewall Management Center (FMC) Software could allow an unauthenticated, remote attacker to execute arbitrary Java code as root\u0026nbsp;on an affected device.\r\n\r\nThis vulnerability is due to insecure deserialization of a user-supplied Java byte stream. An attacker could exploit this vulnerability by sending a crafted serialized Java object to the web-based management interface of an affected device. A successful exploit could allow the attacker to execute arbitrary code on the device and elevate privileges to root.\r\nNote: If the FMC management interface does not have public internet access, the attack surface that is associated with this vulnerability is reduced.","status":"published","published":"2026-03-04T18:16:27.153Z","modified":"2026-06-17T10:17:10.937Z","cvss":[{"version":"3.1","score":10,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H","level":"critical","assessor":"secondary"}],"cwes":["CWE-502"],"updated_at":"2026-11-02T14:12:07.852448Z"}]}}