CVE-2026-20343

A vulnerability in a critical API for Cisco Secure FMC Software could allow an unauthenticated, remote attacker to download sensitive files and use unbounded disk space. This vulnerability exists because a critical API lacks authentication. An attacker could exploit this vulnerability by repeatedly invoking the API. A successful exploit could allow the attacker to download sensitive files that should be restricted and consume disk space so the device could become unresponsive, causing a DoS condition.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-fmc-mulivulns-4PsnFwvx

Configurations

No configuration.

History

16 Sep 2026, 21:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-16 21:17

Updated : 2026-09-18 15:17

NVD link : CVE-2026-20343

Mitre link : CVE-2026-20343

CVE.ORG link : CVE-2026-20343

JSON object : View

Products Affected

No product.

CWE

CWE-306

Missing Authentication for Critical Function

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