CVE-2026-20343

HighCVSS 7.5/10Last modified Sep 18, 2026

Description

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.

Metrics

CVSS 3.1 7.5/10CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Weakness enumeration

CWE-306

Affected software

Source: the vendor's advisory (CNA). NVD analysis pending.

No affected versions have been published.

Timeline

Published: Sep 16, 2026
Last modified: Sep 18, 2026
NVD status: Awaiting Analysis

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