# [CRIT] CISA KEV: CVE-2025-20393 — Cisco Multiple Products Improper Input Validation Vulnerability

**Source:** CISA KEV
**Published:** 2025-12-17
**Article:** https://www.cisa.gov/known-exploited-vulnerabilities-catalog

## Threat Profile

CISA KEV entry. The U.S. federal "Known Exploited Vulnerabilities" catalog only adds CVEs that have been **observed exploited in the wild**. Federal civilian agencies are required to remediate by the published due date; the same prioritisation logic applies to any sensible enterprise SOC.

Vendor / Product: **Cisco Multiple Products Improper Input Validation**

## Indicators of Compromise

- CVE-2025-20393 — match against your vulnerability scanner

## MITRE ATT&CK

- **T1190 — Exploit Public-Facing Application** (KEV implies active exploitation against exposed assets)

## Recommended hunts

Standard asset-exposure hunt — the canonical Splunk SPL and Defender KQL
live once in [`../_TEMPLATES.md#asset-exposure`](../_TEMPLATES.md#asset-exposure).
Substitute this CVE wherever the template references `<CVE>`:

- **CVE:** `CVE-2025-20393`

## Why this matters

Anything in CISA KEV is *currently* being exploited. Even if your scanners say "not vulnerable" because of patches, it's worth one quick check across your fleet — patch lag is the silent killer. Federal due-date dates also frequently match the timing your organisation will be asked about by auditors / regulators.

## Source body

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. Vendor: Cisco, Product: Multiple Products. Federal patch due: 2025-12-24. CVE-2025-20393