CVE-2026-76413 describes a vulnerability in the Cisco ASDM SSO handler component of Cisco Secure FMC Software. The flaw is due to improper handling of the ASDM SSO token, which can be forged by an unauthenticated remote attacker. Exploiting this allows the attacker to authenticate as the ASDM administrator user without credentials. Repeated exploitation can prevent legitimate administrators from accessing the ASDM interface by locking them out.

An unauthenticated remote attacker can gain administrative access to the Cisco ASDM interface, potentially leading to unauthorized configuration changes or denial of service by locking out legitimate administrators. The CVSS score of 8.2 (high) reflects the ease of exploitation (network vector, no privileges or user interaction required) and the significant impact on availability and integrity.

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. No official fix or patch information is provided in the available data. Until a patch is available, monitor Cisco advisories for updates and consider restricting network access to the ASDM interface to trusted sources to reduce exposure.