CVE-2026-76423: Cisco Identity Services Engine Software · Authentication Bypass by Spoofing
Affects Cisco Identity Services Engine SoftwareSource CVE Database V5
Not known to be exploited · CVSS 10.0 Critical.
Data as of 31 Oct 2026, 20:20 UTC
- EPSS
- 0.5% chance of exploitation in 30 days – higher than 47% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:LExploitation evidence
Disclosed: evidence found.
CVE published 16 Sep 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 31 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| CiscoCisco Identity Services Engine Software | Affected
| Fixed in– |
| CiscoCisco ISE Passive Identity Connector | Affected
| Fixed in– |
AI-suggested
Until a fix is available, restrict access to the REST API port to trusted networks and monitor for suspicious activity targeting this interface.
Description
CVE-2026-76423 is a critical authentication bypass vulnerability in the REST API of Cisco Identity Services Engine (ISE) software versions 3.1.0, 3.2.0, 3.3.0, 3.4.0, and 3.5.0. It allows an unauthenticated remote attacker to gain administrative access by exploiting insufficient authorization checks on the REST API web service. Successful exploitation enables reading and modifying ISE configuration and identity data with administrative privileges.