Exploited vulnerabilities / CVE-2025-20393
Confirmed exploited · privilege escalation · Cisco Multiple ProductsCVE-2025-20393
Cisco Multiple Products privilege escalation, confirmed exploited in the wild.
Cisco Secure Email Gateway, Secure Email, AsyncOS Software, and Web Manager appliances contains an improper input validation vulnerability that allows threat actors to execute arbitrary commands with root privileges on the underlying operating system of an affected appliance.
| CISA's name for it | Cisco Multiple Products Improper Input Validation Vulnerability |
|---|---|
| Vendor and product | Cisco · Multiple Products |
| Type | privilege escalation · CWE-20 |
| Exploited | Confirmed by CISA listed 17 December 2025 |
| Likelihood | one of the most likely to be exploited of every vulnerability tracked |
| Deadline | 24 December 2025 · already passed |
| Used in ransomware | Not reported |
| Advisories | sec.cloudapps.cisco.com ↗ · nvd.nist.gov ↗ |
Three steps, in this order
Install the update on every affected system, servers and workstations alike.
Escalation bugs are chained after a first foothold: check for other exposures an attacker could start from.
Review who holds administrative rights, and alert on new ones.
| CISA's required action | Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable. |
|---|
Know before someone else finds it
Threat Landscape Monitoring fingerprints the software your internet-facing hosts disclose and matches it, every day, against this list and the exploitation scores. When a new entry touches something you run, you are told once, with the host and the fix. The free plan covers one domain.
CVE-2025-20393 in short
Is CVE-2025-20393 being exploited?
Yes. CISA added CVE-2025-20393 to its Known Exploited Vulnerabilities catalogue on 17 December 2025, which it does only on evidence of exploitation in the wild.
What is the CISA deadline for CVE-2025-20393?
US federal agencies must remediate it by 24 December 2025. Everyone else should treat that date as the latest safe point to patch an internet-facing system.
How likely is CVE-2025-20393 to be exploited in the next 30 days?
FIRST's Exploit Prediction Scoring System gives it 32%, the 98th percentile of every CVE it scores.
How do I fix CVE-2025-20393?
Install the update on every affected system, servers and workstations alike. Escalation bugs are chained after a first foothold: check for other exposures an attacker could start from. Review who holds administrative rights, and alert on new ones.
Other Cisco vulnerabilities being exploited
| CVE | Product | Type | Listed |
|---|---|---|---|
| CVE-2026-20320 | BroadWorks | exploited vulnerability | 10 November 2026 |
| CVE-2026-76418 | Secure Firewall ASA Software and Cisco Secure FTD Software | denial of service | 29 October 2026 |
| CVE-2026-76519 | Secure Email Gateway | path traversal | 14 October 2026 |
| CVE-2026-76504 | Catalyst SD-WAN Manager | privilege escalation | 30 September 2026 |
| CVE-2026-76460 | Identity Services Engine | privilege escalation | 16 September 2026 |
| CVE-2026-76461 | Secure Email Gateway | SQL injection | 14 September 2026 |
Sources: CISA Known Exploited Vulnerabilities catalogue (released 10 November 2026) and FIRST EPSS. Page compiled automatically by SAK T.L.M, the threat-intelligence tool of SAK T.E.C, on 13 November 2026.