Vulnerability report

Active exploitation observed Confirmed confidence In CISA KEV

CVE-2025-20281

Cisco ISE API Unauthenticated Remote Code Execution Vulnerability

Cisco Identity Services Engine Software · 3.3.0

Watch CVE-2025-20281 Browse KEV feed
Severity
CVSS 10.0 · Critical
Confidence
Confirmed
Exploit status
Observed in sensors
EPSS
97.6%
First observed
28 Jun 2026
Last observed
08 Oct 2026

Decision summary

What security teams need to know first

Direct answers before the deeper technical record.

What it is

CVE-2025-20281 is an unauthenticated Cisco ISE API Unauthenticated Remote Code Execution Vulnerability. A vulnerability in a specific API of Cisco ISE and Cisco ISE-PIC could allow an unauthenticated, remote attacker...

Is it exploited?

Yes. Previdian sensors observed exploitation attempts with confirmed confidence. Listed in CISA KEV. Also confirmed by third-party sources.

Who is affected?

Cisco Identity Services Engine Software 3.3.0.

What should we do?

Patch immediately, validate internet-facing exposure, and monitor for matching requests.

Overview

Cisco ISE API Unauthenticated Remote Code Execution Vulnerability

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 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.

Cisco Affected
Cisco Identity Services Engine Software
3.3.0 3.3 Patch 2 3.3 Patch 1 3.3 Patch 3 3.4.0 3.3 Patch 4 3.4 Patch 1 3.3 Patch 5 3.3 Patch 6
Published
25 Jun 2025
Exploitation Reported
01 Jun 2026
Attack vector
Remote
Complexity
Low
Privileges
None
User interaction
None

Tags

cisa nuclei_scanner edge

CVE References

  • CVE Record CVE.org · CVE Record https://www.cve.org/CVERecord?id=CVE-2025-20281
  • cisco-sa-ise-unauth-rce-ZAd2GnJ6 sec.cloudapps.cisco.com · CVE Record https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurity...

Exploitation evidence

Why Previdian marks this CVE as exploited

Third-party attestation and first-party sensor observation are shown separately so teams can judge the evidence chain.

Exploited in the wild

CVE

Recorded 01 Jun 2026

A trusted third party reported exploitation.

Active exploitation observed

Previdian sensor

First observed 19 Jul 2026

Previdian first observed exploitation attempts targeting this vulnerability in our honeypot sensors.

Proof of concept available

Nuclei Templates

Recorded 12 Jun 2026

Public scanner or PoC coverage increases practical exploitability.

Known exploited vulnerability sources

Per-source evidence links for KEV attestations are available through the Previdian Pro API.

Learn about Pro API access
Source Added
CVE First 2026-06-01 10:37 UTC
CISA 2026-06-02 14:06 UTC
Previdian Sensors 2026-08-13 15:11 UTC

Operational indicators for this CVE are listed under Detection.

Sensor telemetry

First-party evidence of exploitation activity

Previdian sensors recorded exploitation attempts targeting this vulnerability. The cards and chart show volume, unique attackers, and daily activity.

40

Attempts observed

29

Unique attacker IPs

12

Attacker countries

AE · BG · CH · CN · DE · FR · HK · IN · JP · NL · SG · US

10

Sensors observed

CVE-2025-20281 exploitation attempts over the last 85 days

Daily events observed by Previdian sensors

Updated 10 Oct 2026

0
8
0
0
0
1
0
0
0
0
0
0
2
0
2
1
1
0
0
0
0
0
1
0
0
1
1
0
0
0
2
0
0
1
0
0
0
0
0
0
0
0
0
0
0
1
2
0
0
0
0
0
1
1
0
0
0
0
0
2
0
0
0
1
0
0
0
1
1
1
0
1
0
0
1
3
0
0
0
0
1
0
2
0
0
18 Jul 4 Aug 21 Aug 7 Sep 10 Oct

First observed 28 Jun 2026 · Last observed 08 Oct 2026

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Detection

Operational artifacts and observed signals

Make the evidence actionable in scanner, SOC, and edge-control workflows.

Observed signals

Request targets
User-Agents
Callback hosts
1
13
2

Request targets and User-Agents available in Pro. Callback host details available in Enterprise.

Virtual patch status

No Previdian virtual patch is currently available. Future rules ship for ModSecurity, Cloudflare, and AWS WAF.

Learn about virtual patches →

Attacker IP Indicators

Attacker IP indicators observed · available in Pro and Enterprise.

Sensor-derived attacker IP indicators are available to Pro and Enterprise accounts under Detection and through the Pro API.

Learn about Pro API access

Scanner Artifacts

Scanner and exploit-framework references linked to this CVE.

Scanner Reference Detected
Nuclei https://github.com/projectdiscovery/nuclei-templates/blob/main/http/cves/2025/CVE-2025-20281.yaml 01 Jun 2026

Risk and context

Severity, weaknesses, and research context

CVSS v3.1

10.0 Critical

Potential damage if exploited. Separate from whether attackers are using it.

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

EPSS

97.6%

Estimated chance of exploitation in the next 30 days. Previdian's warning comes from evidence, not this score.

Weaknesses

Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection') CWE-74

Potential Proof of Concepts

These PoCs are unverified and could contain malware. Use at your own risk.

Cisco ISE - Remote Code Execution

nuclei · Created Unknown

Timeline

From disclosure to observed exploitation

  1. 02:11 UTC

    Observed by Previdian sensors

    Evidence-backed exploitation signal

  2. 10:58 UTC

    Indicators of compromise added (30)

    Indicators of compromise recorded

  3. 14:21 UTC

    Public PoC available

    Public proof-of-concept code published

  4. 14:06 UTC

    Added to CISA KEV

    Listed in the CISA Known Exploited Vulnerabilities catalog

  5. 15:34 UTC

    Nuclei template available

    Scanner coverage available

  6. 10:37 UTC

    Added to Previdian KEV Feed

    High-confidence, third-party attested exploitation

  7. 16:11 UTC

    CVE published

    Vulnerability disclosed publicly

  8. 19:15 UTC

    CVE ID reserved

    Identifier reserved by the CNA

Pro API

Automate this intelligence

Confidence, exploit status, sensor telemetry, PoCs, scanner integrations, mentions, and tags are available programmatically for VM, SOC, and CTI workflows.

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  • Evidence confidence and provenance
  • First-party sensor telemetry
  • PoC and scanner references
  • Affected versions and enrichment
  • Automation-ready JSON delivery

GET /api/v2/pro/kevs/CVE-2025-20281

Free JSON includes basic KEV fields 
{
  "cve_id": "CVE-2025-20281",
  "confidence": "Confirmed",
  "cvss_score": 10.0,
  "cvss_estimated": false,
  "epss_score": 0.97601,
  "exploit_status": {
    "exploited_in_the_wild": true,
    "active_exploitation_observed": true
  },
  "sensor_telemetry": { "attempts": 40, "sensors": 10 }
}