Cisco Secure Firewall Management Center Software Single Sign-On Token Forgery of Administrator Account Vulnerability

published 2026-09-16 53 d ago modified 2026-09-18 52 d ago also EUVD-2026-81120

cvss: 8.2; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.5%; EPSS 0.5% chance of exploitation in 30 days, percentile 39%
public exploits: 0; none known

A vulnerability in Cisco Adaptive Security Device Manager (ASDM) single sign-on (SSO) handler for Cisco Secure FMC Software could allow an unauthenticated, remote attacker to log in as the Cisco ASDM administrator user.

This vulnerability is due to improper management of the Cisco ASDM SSO token. An attacker could exploit this vulnerability by performing session token forgery techniques. A successful exploit could allow the attacker to log in as the administrator user and, by repeating this action, keep legitimate administrators locked out of the ASDM indefinitely.

CISA SSVC

Exploitation: none
Automatable: yes
Technical impact: partial
Assessed: 53 d ago (2026-09-17)

Exploit prediction

0.46% chance of exploitation in the next 30 days, higher than 39% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.1	8.2	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H

Affected products

Cisco Cisco Secure Firewall Management Center (FMC)

Classification

Weakness

CWE-1259 Improper Restriction of Security Token Assignment

References

sec.cloudapps.cisco.com /security/center/content/CiscoSecurityAdvisory/cisco-sa-fmc2-multivulns-HXgcqRG

Sources

CVE List CVE-2026-76413
NVD CVE-2026-76413

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Summary