Cyber Resilience

CVE-2025-20276

Low

Published: 04 June 2025

Published
04 June 2025
Modified
22 July 2025
KEV Added
Patch
CVSS Score v3.1 3.8 CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:L/A:N
EPSS Score 0.0151 81.6th percentile
Risk Priority 9 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2025-20276 is a low-severity Deserialization of Untrusted Data (CWE-502) vulnerability in Cisco Unified Contact Center Express. Its CVSS base score is 3.8 (Low).

Operationally, ranked in the top 18.4% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

Deeper analysis

A vulnerability in the web-based management interface of Cisco Unified CCX stems from insecure deserialization of Java objects, tracked as CWE-502. The flaw affects the contact center application and carries a CVSS 3.1 score of 3.8.

An authenticated remote attacker who possesses valid administrative credentials can send a crafted Java object to the interface. Successful exploitation permits arbitrary code execution on the underlying operating system as a low-privilege user and may enable subsequent privilege escalation to root.

The Cisco Security Advisory cisco-sa-uccx-multi-UhOTvPGL at https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-uccx-multi-UhOTvPGL addresses the issue.

EPSS remains flat at 0.0151 with no material increase after disclosure.

EU & UK References

Vulnerability details

A vulnerability in the web-based management interface of Cisco Unified CCX could allow an authenticated, remote attacker to execute arbitrary code on an affected device. To exploit this vulnerability, the attacker must have valid administrative credentials.  This vulnerability is due…

more

to insecure deserialization of Java objects by the affected software. An attacker could exploit this vulnerability by sending a crafted Java object to an affected device. A successful exploit could allow the attacker to execute arbitrary code on the underlying operating system of an affected device as a low-privilege user. A successful exploit could also allow the attacker to undertake further actions to elevate their privileges to root.

CWE(s)

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

cisco
unified contact center express
10.0\(1\)su1, 10.0\(1\)su1es04, 10.5\(1\), 10.5\(1\)su1, 10.5\(1\)su1es10

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-502

Penetration testing supplies malicious serialized objects, detecting unsafe deserialization and supporting corrective actions.

addresses: CWE-502

Evaluation of untrusted data handling (deserialization testing) reveals unsafe processing, which the required remediation process addresses.

addresses: CWE-502

Untrusted serialized data can be deserialized and observed inside the chamber, blocking gadget-chain exploitation outside the sandbox.

addresses: CWE-502

Validates or rejects untrusted serialized data before deserialization occurs.

addresses: CWE-502

Identifies and blocks malicious code introduced through deserialization of untrusted data at system boundaries.

addresses: CWE-502

Integrity verification of serialized information can detect tampering before deserialization occurs.

addresses: CWE-502

Provenance of associated data allows detection of untrusted sources before deserialization or processing occurs.

References