Cisco Firepower Management Center Software Common Access Card Authentication Bypass Vulnerability

published 2020-10-21 6 y ago modified 2026-06-17 4 mo ago also EUVD-2020-24681

cvss: 8.1; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 1.1%; EPSS 1.1% chance of exploitation in 30 days, percentile 66%
public exploits: 0; none known

A vulnerability in the Common Access Card (CAC) authentication feature of Cisco Firepower Management Center (FMC) Software could allow an unauthenticated, remote attacker to bypass authentication and access the FMC system. The attacker must have a valid CAC to initiate the access attempt. The vulnerability is due to incorrect session invalidation during CAC authentication. An attacker could exploit this vulnerability by performing a CAC-based authentication attempt to an affected system. A successful exploit could allow the attacker to access an affected system with the privileges of a CAC-authenticated user who is currently logged in.

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: total
Assessed: 23 mo ago (2024-11-13)

Exploit prediction

1.14% chance of exploitation in the next 30 days, higher than 66% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.1	8.1	CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
NVD	3.1	8.1	CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
NVD	2.0	6.8	AV:N/AC:M/Au:N/C:P/I:P/A:P

Affected products

Cisco Cisco Firepower Management Center

Classification

Weakness

CWE-287 Improper Authentication

References

tools.cisco.com /security/center/content/CiscoSecurityAdvisory/cisco-sa-fmc-cacauthbyp-NCLGZm3Q
vendor-advisory

Sources

CVE List CVE-2020-3410
NVD CVE-2020-3410

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Summary