CVE-2025-20281CRITICAL · 10.0Patch second

Cisco Identity Services Engine Injection Vulnerability

CVE-2025-20281 is a security vulnerability in Cisco Identity Services Engine, added to CISA KEV on July 28, 2025. Patch order: second of four.

Published (added to CISA KEV) · Updated · Cisco Identity Services Engine

What is CVE-2025-20281?

Cisco Identity Services Engine contains an injection vulnerability in a specific API of Cisco ISE and Cisco ISE-PIC due to insufficient validation of user-supplied input allowing an attacker to exploit this vulnerability by submitting a crafted API request. Successful exploitation could allow an attacker to perform remote code execution and obtaining root privileges on an affected device.

VulnCheck tracked exploitation 15 days before CISA's KEV listing. VulnCheck's broader catalog of in-the-wild exploitation evidence picked this up before it landed on CISA's formal list. Per-CVE fact about this entry; not a population claim about lead time in general.

Who is affected by CVE-2025-20281?

Affects anyone with Cisco networking or security appliances on their network — typically a firewall, switch, or remote-access VPN. That device controls traffic to and from every workstation; exploitation can mean an attacker pivots inside the network without touching any user device.

What should I do about CVE-2025-20281?

Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

The action above is CISA's wording. The directive it names, BOD 22-01, was revoked by BOD 26-04 on June 10, 2026; CISA's catalog still carries the older text for this entry.

If you don't have someone in-house to verify the patch deployed across every endpoint — or you're not sure whether you're affected — that's exactly the kind of triage we do. Request a free review.

Insurance readiness

Your insurer will ask if this is patched.

Unpatched entries on CISA's Known Exploited Vulnerabilities list are exactly what cyber-insurance carrier questionnaires probe for, and knowing which controls they check is how you keep a renewal from stalling.

Get the free carrier questionnaire →

Severity

CVSS base score: 10.0 — CRITICAL

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

Weakness classification: CWE-74

CVSS, severity, and CWE data from the National Vulnerability Database (NVD). This product uses data from the NVD API but is not endorsed or certified by the NVD.

CISA due date

CISA's listed due date: August 18, 2025.

Federal civilian agencies work under CISA's Binding Operational Directive 26-04, which replaced BOD 22-01 on June 10, 2026. It sets the deadline for each affected system by:

  • How exposed that system is to the internet
  • Whether the attack can be automated
  • How much control it gives an attacker

Its table gives catalogued vulnerabilities 3 or 14 days.

None of this binds a private business, but treat the date as a strong recommendation, especially if you handle regulated data (HIPAA, GLBA, ABA model rules).

EPSS

EPSS score: 97.6% — higher than 100% of all scored CVEs.

EPSS estimates the probability of exploitation activity in the next 30 days. Every entry on this site is already confirmed exploited, so read it as relative urgency among the things you still have open, not as permission to wait.

Score dated 2026-10-16, from the FIRST.org Exploit Prediction Scoring System.

Other exploited Cisco Identity Services Engine entries

More CISA KEV entries for Cisco Identity Services Engine. Same product line, same actively-exploited status.

Source

This entry comes from CISA's Known Exploited Vulnerabilities catalog, public US-Government data we pull daily. The plain-language framing and the what-to-do guidance above are ours. View the original entry on cisa.gov.

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