CVE-2026-20242 (GCVE-0-2026-20242)
Vulnerability from cvelistv5
Published
2026-09-16 20:08
Modified
2026-09-18 03:55
Severity ?
9.8 (Critical) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CWE
  • CWE-502 - Deserialization of Untrusted Data
Summary
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 root on an affected device. This 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. Notes: This vulnerability can be exploited only by an attacker who has control of a host in the external database access list. If the FMC management interface does not have public internet access, the attack surface that is associated with this vulnerability is reduced.
References
Impacted products
Vendor Product Version
Cisco Cisco Secure Firewall Management Center (FMC) Version: 7.0.0
Version: 7.0.0.1
Version: 7.0.1
Version: 7.0.1.1
Version: 7.0.2
Version: 7.2.0
Version: 7.0.2.1
Version: 7.0.3
Version: 7.2.0.1
Version: 7.0.4
Version: 7.2.1
Version: 7.0.5
Version: 7.3.0
Version: 7.2.2
Version: 7.3.1
Version: 7.2.3
Version: 7.2.3.1
Version: 7.2.4
Version: 7.0.6
Version: 7.2.4.1
Version: 7.2.5
Version: 7.3.1.1
Version: 7.4.0
Version: 7.0.6.1
Version: 7.2.5.1
Version: 7.4.1
Version: 7.2.6
Version: 7.4.1.1
Version: 7.0.6.2
Version: 7.2.7
Version: 7.2.5.2
Version: 7.3.1.2
Version: 7.2.8
Version: 7.6.0
Version: 7.4.2
Version: 7.2.8.1
Version: 7.0.6.3
Version: 7.4.2.1
Version: 7.2.9
Version: 7.0.7
Version: 7.7.0
Version: 7.4.2.2
Version: 7.2.10
Version: 7.6.1
Version: 7.4.2.3
Version: 7.0.8
Version: 7.6.2
Version: 7.7.10
Version: 7.2.10.1
Version: 7.0.8.1
Version: 7.6.2.1
Version: 7.2.10.2
Version: 7.7.10.1
Version: 7.4.2.4
Version: 7.4.3
Version: 7.6.3
Version: 7.7.11
Version: 7.6.4
Version: 10.0.0
Version: 7.4.4
Version: 7.4.5
Version: 7.0.9
Version: 7.2.11
Version: 7.7.12
Version: 7.6.5
Version: 7.4.6
Version: 10.0.1
Version: 7.4.7
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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.\"}], \"problemTypes\": [{\"descriptions\": [{\"lang\": \"en\", \"type\": \"cwe\", \"cweId\": \"CWE-502\", \"description\": \"Deserialization of Untrusted Data\"}]}], \"providerMetadata\": {\"orgId\": \"d1c1063e-7a18-46af-9102-31f8928bc633\", \"shortName\": \"cisco\", \"dateUpdated\": \"2026-09-16T20:08:27.904Z\"}}}",
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