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CVE-2026-20155 Cisco CVE debrief

A vulnerability in the web-based management interface of Cisco Evolved Programmable Network Manager (EPNM) could allow an authenticated, remote attacker with low privileges to access sensitive information that they are not authorized to access. This vulnerability is due to improper authorization checks on a REST API endpoint of an affected device. An attacker could exploit this vulnerability by querying the affected endpoint. A successful exploit could allow the attacker to view session information of active Cisco EPNM users, including users with administrative privileges, which could result in the affected device being compromised. The vulnerability has a CVSS score of 8 and a severity rating of HIGH. Cisco has released an advisory to address this vulnerability.

Vendor
Cisco
Product
Evolved Programmable Network Manager
CVSS
HIGH 8
CISA KEV
Not listed in stored evidence
Original CVE published
2026-04-01
Original CVE updated
2026-07-02
Advisory published
2026-04-01
Advisory updated
2026-07-02

Who should care

Organizations using Cisco Evolved Programmable Network Manager (EPNM) should be aware of this vulnerability and take steps to mitigate it. Specifically, administrators of EPNM systems should review their configurations and ensure that they are running the latest version of the software. Additionally, network administrators and security teams should be vigilant for any suspicious activity that could indicate exploitation of this vulnerability.

Technical summary

The vulnerability in Cisco Evolved Programmable Network Manager (EPNM) is caused by improper authorization checks on a REST API endpoint. This allows an authenticated, remote attacker with low privileges to access sensitive information that they are not authorized to access. The vulnerability can be exploited by querying the affected endpoint, potentially allowing the attacker to view session information of active Cisco EPNM users, including those with administrative privileges.

Defensive priority

High priority should be given to patching or mitigating this vulnerability, as it could allow an attacker to gain unauthorized access to sensitive information. Administrators should review their EPNM configurations and ensure that they are running the latest version of the software.

Recommended defensive actions

  • Review and apply the latest security patches for Cisco Evolved Programmable Network Manager (EPNM).
  • Monitor network activity for suspicious behavior that could indicate exploitation of this vulnerability.
  • Implement additional security measures, such as multi-factor authentication and strict access controls, to reduce the risk of exploitation.
  • Conduct regular security audits and vulnerability assessments to identify and address potential weaknesses.
  • Ensure that incident response plans are up-to-date and include procedures for responding to potential exploitation of this vulnerability.

Evidence notes

The CVE record for CVE-2026-20155 provides detailed information about the vulnerability, including its CVSS score and severity rating. The Cisco Security Advisory provides guidance on mitigating the vulnerability. The NVD entry for CVE-2026-20155 offers additional information about the vulnerability and its potential impact.

Official resources

This article was generated with AI assistance based on the supplied source corpus and is intended for informational purposes only. It is not an official statement from Cisco or any other vendor and should not be considered as such.