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Mallory
Critical

Authenticated OS Command Execution in Cisco Identity Services Engine (ISE)

IdentifiersCVE-2026-20180CWE-22· Improper Limitation of a Pathname…

CVE-2026-20180 is a critical authenticated remote code/command execution vulnerability in Cisco Identity Services Engine (ISE). The flaw is in the ISE web management interface and is caused by insufficient validation of user-supplied input in HTTP request handling. Cisco states that an attacker with at least Read Only Admin credentials can send a crafted HTTP request to an affected device and execute arbitrary commands on the underlying operating system. Successful exploitation can yield user-level access to the underlying OS and then allow privilege escalation to root. Supporting reporting also associates the issue with input-validation weaknesses described as path traversal and command injection behavior, but the primary vendor description attributes it to insufficient validation of user input.

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ANALYST BRIEF

Impact, mitigation & remediation

What it means. What to do now. Patch path, mitigations, and the assume-compromise checklist.

Impact

What an attacker gets, and what they’ve been doing with it.

Successful exploitation allows an authenticated remote attacker to execute arbitrary commands on the underlying operating system of the affected Cisco ISE device. The attacker can obtain user-level shell or OS access and then escalate privileges to root, resulting in full compromise of the appliance. In single-node ISE deployments, exploitation may also render the node unavailable, creating a denial-of-service condition that prevents endpoints that have not already authenticated from accessing the network until the node is restored.

Mitigation

If you can’t patch tonight, do this now.

No workaround is available according to Cisco. Until patching is completed, reduce exposure by tightly restricting network access to the ISE management interface, minimizing and reviewing assignment of Read Only Admin and other administrative roles, and monitoring ISE web access logs for anomalous crafted HTTP requests or suspicious activity originating from administrative accounts, especially Read Only Admin accounts.

Remediation

Patch, then assume compromise.

Apply Cisco's fixed software releases for Cisco ISE. Based on the provided content, Cisco fixed CVE-2026-20180 in ISE 3.2 Patch 8, 3.3 Patch 8, and 3.4 Patch 4. Cisco ISE 3.5 is reported as not vulnerable. Deployments running versions earlier than 3.2 require migration to a fixed supported release because no direct patch is available for those older versions. Cisco published the fix in advisory cisco-sa-ise-rce-4fverepv on April 15, 2026.
PUBLIC EXPLOITS

Exploits

No valid public exploits. Mallory filtered out 1 candidate as fakes, detection scripts, or README-only repos.

VALID 0 / 1 TOTALView more in app

All candidate exploits were filtered out by Mallory's validation.

EXPOSURE SURFACE

Affected products & vendors

Products and vendors Mallory has correlated with this vulnerability. Open in Mallory to drill down to specific CPE configurations and version ranges.

VendorProductType
Cisco SystemsIdentity Services Engineapplication

Vendor-confirmed product mapping. Mallory continuously reconciles this list against your asset inventory.

What this page doesn’t show

The version that knows your environment.

This page is what’s public. Mallory adds the parts that aren’t: which of your assets are affected, which adversaries are exploiting it right now, which detections to deploy, and what to do tonight.
Exposure mapping

Query your assets running an affected version, and investigate the blast radius.

Threat actor evidence

Every observed campaign linking this CVE to a named adversary.

Associated malware

Malware families riding this exploit, with evidence and IOCs.

Detection signatures

YARA, Sigma, Snort, and vendor rules, auto-deployed to your SIEM.

Vendor-by-vendor mapping

Cross-references every affected SKU, including bundled OEM variants.

Social activity5

Community discussion across Reddit, Mastodon, and other social sources.