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Fencer Intel
critical 9.9

CVE-2025-20124 in the critical feed json

Cisco Identity Services Engine Java Deserialization Vulnerability

published last yr. modified 4mo ago also EUVD-2025-2152

cvss
9.9
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
18.6%
EPSS 18.6% chance of exploitation in 30 days, percentile 97%
public exploits
1
Exploit-DB

Summary

A vulnerability in an API of Cisco ISE could allow an authenticated, remote attacker to execute arbitrary commands as the root user on an affected device.

This vulnerability is due to insecure deserialization of user-supplied Java byte streams by the affected software. An attacker could exploit this vulnerability by sending a crafted serialized Java object to an affected API. A successful exploit could allow the attacker to execute arbitrary commands on the device and elevate privileges. Note: To successfully exploit this vulnerability, the attacker must have valid read-only administrative credentials. In a single-node deployment, new devices will not be able to authenticate during the reload time.

Patch / fix

  • cisco identity_services_engine 3.1

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Timeline

  1. Published
  2. First public exploit (EDB-52396)

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
total
Assessed
last yr.

Exploit prediction

18.62% chance of exploitation in the next 30 days, higher than 97% of all scored CVEs (FIRST EPSS, 2026-11-11).

Exploits and checks

  • EDB-52396 Cisco ISE 3.0 - Remote Code Execution (RCE) remote, 2025-08-11

CVSS scores

assigned by version score vector
CNA 3.1 9.9 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:H/A:H
NVD 3.1 7.2 CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H

Affected products

  • Cisco Cisco Identity Services Engine Software
  • Cisco Cisco ISE Passive Identity Connector

Classification

Weakness
  • CWE-502 Deserialization of Untrusted Data

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.