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CISA KEV · ACTIVELY EXPLOITED
CRITICAL severity

CVE-2025-20281

CRITICAL

CVE-2025-20281 is a critical-severity (CVSS 10) CWE-74 vulnerability in cisco identity services engine. It is in CISA's Known Exploited Vulnerabilities catalog (added 2025-07-28) — treat it as actively exploited and patch now. O3 Security detects and blocks CVE-2025-20281 exploitation at runtime via eBPF exploit-chain detection and L7 egress monitoring, even on unpatched systems.

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.…

Published
Jun 25, 2025
Updated
Jun 17, 2026
Affected
2 products
Patched
See advisory
Exploits
3 known
Exploitation data as of Aug 27, 2026 · OSV.dev, NVD, CISA KEV, FIRST.org (EPSS)

Exploitation Status

Actively exploited in the wild

  • Confirmed by CISA's Known Exploited Vulnerabilities catalog on 2025-07-28. Federal agencies were required to remediate by 2025-08-18.
  • CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
  • A successful exploit gives an attacker total control of the affected component, not partial access.

Exploitation and automatability from CISA (KEV catalog and SSVC triage) for CVE-2025-20281.

EPSS Exploitation Probability

via FIRST.org ↗
97.1%probability of exploitation in next 30 days
Very High Risk+62.93%
Lower risk than most CVEs100th percentile — riskier than 100% of all scored CVEsHighest risk
3.10%35.4%67.7%100.0%24.8%34.2%97.1%Feb 26Jun 26Aug 26

EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.

How urgent is this, really

CVE-2025-20281 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE sits: patch-first territory.

Where this sits among everything scored

Of 0 CVEs with a current EPSS score, this one falls in the ≥ 90% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.

Description

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.

Affected Products

2 products · 18 configurations
Application
identity services enginecisco
2 versions
3.3.03.4.0
Application
identity services engine passive identity connectorcisco
2 versions
3.3.03.4.0
Exploits & PoCs
3

Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.

Detection & mitigation playbook

Vendor / appliance
  1. Detect

    Inventory every cisco identity services engine deployment and check each version against the affected-products list above. Because the exploit targets the running system rather than your application code, also watch for remote code execution at the network and runtime layer — O3 flags the exploit behaviour from runtime telemetry and egress traffic even before a vulnerable build is confirmed.

  2. Remediation status

    No patch has shipped for CVE-2025-20281 yet — track the cisco identity services engine advisory for a fixed release and apply the workarounds below in the meantime.

  3. Mitigate without a patch

    Cut exposure now: restrict the management/admin interface to trusted networks, segment the device, and apply the vendor's recommended configuration mitigations and any WAF/IPS signature. O3's runtime protection blocks the exploit chain at execution, holding the line on unpatched or end-of-life systems until you can patch.

  4. How O3 protects you

    O3 detects and blocks CVE-2025-20281 exploitation at runtime: eBPF exploit-chain detection, plus L7 egress monitoring that catches the post-exploitation callback and severs the attacker's outbound channel.

Tailored to CVE-2025-20281. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

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.
O3 Security · Runtime Protection

Is CVE-2025-20281 being exploited in your environment?

O3's eBPF runtime sensors and L7 egress monitoring detect and block the CVE-2025-20281 exploit chain at execution — protecting unpatched and end-of-life systems until the vendor patch is applied.

CVE-2025-20281: Identity Services Engine… | O3 Security