2025-042: Critical Vulnerability in Cisco Secure Email and Web Manager
Actively exploited. At least one CVE in this advisory is listed in the CISA Known Exploited Vulnerabilities catalog — exploitation has been observed in the wild. Treat remediation as urgent.
On December 17, 2025, Cisco released a security advisory for a critical vulnerability affecting Cisco Secure Email Gateway and Cisco Secure Email and Web Manager products. It is recommended to follow Cisco's recommendations to check whether vulnerable appliances have been compromised, and to remediate the issue. There is no patch available for this vulnerability yet.
CSIRTS triage
- What
- A critical vulnerability could allow remote code execution on affected products.
- Who is affected
- Customers using Cisco Secure Email Gateway and Secure Email and Web Manager are affected.
- Urgency
- Remediation is critical as the vulnerability is actively exploited and no patch is available yet.
- Action
- Check for compromised appliances and follow Cisco's recommendations.
AI-assisted analysis generated from the source advisory — verify against the original.
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Details
Original advisory: https://cert.europa.eu/publications/security-advisories/2025-042/
Exploitation outlook
EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.
- Exploitation confirmedCVE-2025-20393Already exploited in the wild (CISA KEV) — the prediction phase is over. Patch now. Riskier than 98% of all EPSS-scored CVEs.
Referenced CVEs
| CVE | CSIRTS overview | External |
|---|---|---|
| CVE-2025-20393 | coverage & exploitation status | NVD · CVE.org |
Same CVEs, other sources
How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.
- criticalexploitedCVE-2025-20393: Cisco Multiple Products Improper Input Validation Vulnerabilitycisa-kev
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