CVE-2025-20139
Cisco Enterprise Chat And Email ≤ 12.6\(1\)es10
Raw vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HSummary
CVE-2025-20139 is a high-severity Incorrect Regular Expression (CWE-185) vulnerability in Cisco Enterprise Chat And Email. Its CVSS base score is 7.5 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Command and Scripting Interpreter (T1059); ranked at the 47th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.
The strongest mitigations our analysis identified map to SA-11 (Developer Testing and Evaluation) and SA-15 (Development Process, Standards, and Tools) — see the control section below for these in your framework.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2025-9561
Vulnerability Data
A vulnerability in chat messaging features of Cisco Enterprise Chat and Email (ECE) could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition. This vulnerability is due to improper validation of user-supplied input to chat entry…
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points. An attacker could exploit this vulnerability by sending malicious requests to a messaging chat entry point in the affected application. A successful exploit could allow the attacker to cause the application to stop responding, resulting in a DoS condition. The application may not recover on its own and may need an administrator to manually restart services to recover.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Mitigating Controls (NIST 800-53 r5) AI
Developer testing and evaluation can discover regex that fails to match or compare data as intended.
Requiring documented development standards and tools reduces the chance that incorrect regular expressions are written into validation or filtering logic.
An SDLC that incorporates security can embed reviews or tooling that catch malformed regular expressions before deployment.
Mitigating Controls (NIST CSF 2.0) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.
Secure SDLC practices directly require correct regex design, testing, and review to avoid improper matching.
Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.
Security testing in development can detect regex-related flaws before release.
Secure development lifecycle includes validation of input-handling constructs such as regex.
Application security requirements can mandate correct regex design and testing.
Secure coding standards directly address proper construction and review of regular expressions.