CVE-2025-20124

CVE-2025-20124 is a critical-severity vulnerability in Cisco Identity Services Engine with a CVSS 3.x base score of 9.9. Its EPSS exploit-prediction score of 17% places it in the 97th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-502.

Key facts

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.

Frequently asked questions

What is CVE-2025-20124?
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.
How severe is CVE-2025-20124?
CVE-2025-20124 has a CVSS 3.x base score of 9.9, rated critical severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity high, and availability high.
Is CVE-2025-20124 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 17% (97th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-20124?
CVE-2025-20124 primarily affects Cisco Identity Services Engine. In total, 22 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2025-20124?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
Does CVE-2025-20124 have an EU (EUVD) identifier?
Yes. CVE-2025-20124 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-2152.
When was CVE-2025-20124 published?
CVE-2025-20124 was published on 2025-02-05 and last updated on 2026-06-17.

References

Affected products (22)

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