9.9

CVE-2025-20124: cisco cisco identity services engine software Deserialization of Untrusted Data

CVSS: 9.9v3.1CriticalAnalyzed
Published 05-02-2025Last modified 26-02-2026
Open JSON

Vulnerability summary

CVE-2025-20124 is a critical (CVSS 9.9) Deserialization of Untrusted Data vulnerability in cisco cisco identity services engine software. EPSS estimates a 18.48% chance of exploitation in the next 30 days, higher than 97.2% of scored vulnerabilities. 1 public exploit is recorded.

Overall risk
70/100
0100
High · default modelHow is this calculated?
CVSS score
9.9/10
010
Critical · v3.1 (CVE.org)
EPSS score
18.48%
0%100%
Medium · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits1exploit-database

Timeline

  1. 05-02-2025
    PublishedVulnerability first disclosed.
  2. 26-02-2026
    Last modifiedVulnerability information updated.

Description

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.

CVSS metrics

2 scores · 2 sources · 1 version

EPSS trend

Probability

18.48%

Chance of exploitation in the next 30 days

Percentile

97%

Versus all other CVEs

30-day change

0.00 pp

From 18.48% on 19-09-2026

19-09-202619-10-2026
EPSS score
18.48%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

1 found
  • exploit-databaseremotemultipleUnverified

    Cisco ISE 3.0 - Remote Code Execution (RCE)

    Maturity: poc

Weaknesses

CWE · root cause

Affected systems

Cisco3 products
  • cisco identity services engine software3.0.0 | 3.0.0 p1 | 3.0.0 p2 | 3.0.0 p3 | 3.1.0 | 3.0.0 p4 | 3.1.0 p1 | 3.0.0 p5 | 3.1.0 p3 | 3.1.0 p2 | 3.0.0 p6 | 3.2.0 | 3.1.0 p4 | 2.7.0 p8 | 3.1.0 p5 | 3.2.0 p1 | 3.0.0 p7 | 3.1.0 p6 | 3.2.0 p2 | 3.1.0 p7 | 3.3.0 | 3.2.0 p3 | 3.0.0 p8 | 3.2.0 p4 | 3.1.0 p8 | 3.2.0 p5 | 3.2.0 p6 | 3.1.0 p9 | 3.3 Patch 2 | 3.3 Patch 1 | 3.3 Patch 3
  • cisco ise passive identity connector3.0.0 | 3.2.0 | 3.1.0 | 3.3.0
  • identity_services_engine< 3.1 | 3.1.0 | 3.1.0:patch1 | 3.1.0:patch2 | 3.1.0:patch3 | 3.1.0:patch4 | 3.1.0:patch5 | 3.1.0:patch6 | 3.1.0:patch7 | 3.1.0:patch8 | 3.1.0:patch9 | 3.2.0 | 3.2.0:patch1 | 3.2.0:patch2 | 3.2.0:patch3 | 3.2.0:patch4 | 3.2.0:patch5 | 3.2.0:patch6 | 3.3.0 | 3.3.0:patch1 | 3.3.0:patch2 | 3.3.0:patch3

1 vendor · 3 products

References

1 links