Cisco has released updates to address a medium-severity security flaw in Identity Services Engine (ISE) and ISE Passive Identity Connector (ISE-PIC) with a public proof-of-concept (PoC) exploit.
The vulnerability, tracked as CVE-2026-20029 (CVSS score: 4.9), resides in the licensing feature and could allow an authenticated, remote attacker with administrative privileges to gain access to sensitive information.
“This vulnerability is due to improper parsing of XML that is processed by the web-based management interface of Cisco ISE and Cisco ISE-PIC,” Cisco said in a Wednesday advisory. “An attacker could exploit this vulnerability by uploading a malicious file to the application.”
Successful exploitation of the shortcoming could allow an attacker with valid administrative credentials to read arbitrary files from the underlying operating system, which the company said should be off-limits even to administrators.
Bobby Gould of Trend Micro Zero Day Initiative has been credited with discovering and reporting the flaw. It affects the following versions –
- Cisco ISE or ISE-PIC Release earlier than 3.2 – Migrate to a fixed release
- Cisco ISE or ISE-PIC Release 3.2 – 3.2 Patch 8
- Cisco ISE or ISE-PIC Release 3.3 – 3.3 Patch 8
- Cisco ISE or ISE-PIC Release 3.4 – 3.4 Patch 4
- Cisco ISE or ISE-PIC Release 3.5 – Not vulnerable
Cisco said there are no workarounds to address the flaw, adding it’s aware of the availability of a PoC exploit code. There are no indications that it has been exploited in the wild.
In tandem, the networking equipment company also shipped fixes for two other medium-severity bugs stemming from the processing of Distributed Computing Environment Remote Procedure Call (DCE/RPC) requests that could allow an unauthenticated, remote attacker to cause the Snort 3 Detection Engine to leak sensitive information or to restart, impacting availability.
Trend Micro researcher Guy Lederfein has acknowledged for reporting the flaws. The details of the issues are as follows –
- CVE-2026-20026 (CVSS score: 5.8) – Snort 3 DCE/RPC denial-of-service vulnerability
- CVE-2026-20027 (CVSS score: 5.3) – Snort 3 DCE/RPC information disclosure vulnerability
They affect a number of Cisco products –
- Cisco Secure Firewall Threat Defense (FTD) Software, if Snort 3 was configured
- Cisco IOS XE Software
- Cisco Meraki software
With vulnerabilities in Cisco products frequently targeted by bad actors, it’s crucial that users update to the latest version for adequate protection.
