Cyber Resilience

CVE-2025-20281

Cisco Identity Services Engine 3.3.0 … 3.4.0

CISA KEVActive ExploitationEUVD ExploitedPublic PoC
Published
25 June 2025
Modified
17 June 2026
KEV Added
28 July 2025
Patch / advisory
CVSS Score v3.1 10.0
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
EPSS Score 0.97 99.9th percentile
Risk Priority 100 floored blend · peak EPSS

Summary

CVE-2025-20281 is a critical-severity Injection (CWE-74) vulnerability in Cisco Identity Services Engine. Its CVSS base score is 10.0 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked in the top 0.1% of CVEs by exploit likelihood; CISA has added it to the Known Exploited Vulnerabilities catalog; a public proof-of-concept is referenced.

The strongest mitigations our analysis identified map to SI-10 (Information Input Validation) — see the control section below for these in your framework.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

A vulnerability in a specific API of Cisco ISE and Cisco ISE-PIC allows unauthenticated remote attackers to execute arbitrary code as root on the underlying operating system. The flaw stems from insufficient validation of user-supplied input and is tracked as CWE-74 with a CVSS score of 10.0.

An attacker can exploit the issue by submitting a crafted API request without any credentials, resulting in full root-level compromise of an affected device. The attack requires no user interaction and can be carried out remotely over the network.

The Cisco Security Advisory cisco-sa-ise-unauth-rce-ZAd2GnJ6 and CISA's Known Exploited Vulnerabilities catalog both address the issue, confirming active exploitation in the wild. The associated EPSS score has reached a peak of 0.3603 with a current value of 0.3348.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

A vulnerability in a specific API of Cisco ISE and Cisco ISE-PIC could allow an unauthenticated, remote attacker to execute arbitrary code on the underlying operating system as root. The attacker does not require any valid credentials to exploit this…

more

vulnerability. This vulnerability is due to insufficient validation of user-supplied input. An attacker could exploit this vulnerability by submitting a crafted API request. A successful exploit could allow the attacker to obtain root privileges on an affected device.

CWE(s)
KEV Date Added
28 July 2025

Related Threats

MITRE ATT&CK Enterprise Techniques

T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
T1221 Template Injection Stealth
Adversaries may create or modify references in user document templates to conceal malicious code or force authentication attempts.
T1659 Content Injection Initial Access
Adversaries may gain access and continuously communicate with victims by injecting malicious content into systems through online network traffic.
T1674 Input Injection Execution
Adversaries may simulate keystrokes on a victim’s computer by various means to perform any type of action on behalf of the user, such as launching the command interpreter using keyboard shortcuts, typing an inline script to be executed,…
T1059 Command and Scripting Interpreter Execution
Adversaries may abuse command and script interpreters to execute commands, scripts, or binaries.
T1059.001 PowerShell Execution
Adversaries may abuse PowerShell commands and scripts for execution.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2025-20337Same product: Cisco Identity Services Engineboth on KEV
CVE-2025-20284Same product: Cisco Identity Services Engine
CVE-2025-20283Same product: Cisco Identity Services Engine
CVE-2025-20216Same vendor: Cisco
CVE-2024-20429Same vendor: Cisco
CVE-2025-20256Same vendor: Cisco
CVE-2025-20265Same vendor: Cisco
CVE-2026-20199Same vendor: Cisco
CVE-2023-20057Same vendor: Cisco
CVE-2019-2725Shared CWE-74both on KEV

Affected Assets

cisco
identity services engine
3.3.0, 3.4.0
cisco
identity services engine passive identity connector
3.3.0, 3.4.0

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)

Validate
Prove the fix (OWASP ASVS)
  • V1.2.1
  • V1.2.3
  • V1.2.5
  • V1.2.8

Mitigating Controls (NIST 800-53 r5) AI

SI-10 directly requires validation of information inputs to reject malformed or special-element content before it reaches downstream parsers.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

Secure SDLC practices directly require input validation and output encoding that prevent injection flaws.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

finds

Security testing in development catches injection vulnerabilities before release.

A.8.15 Logging partial match
finds

Logging supports detection of injection attempts but does not prevent the weakness.

finds

Monitoring activities can identify active injection attacks after they occur.

prevents

Secure development life cycle mandates input validation and output encoding that directly prevent injection flaws.

prevents

Application security requirements explicitly call for controls against injection attacks in software design.

prevents

Secure architecture principles reduce injection surfaces but do not prescribe specific neutralization techniques.

References