Is CVE-2025-20352 being actively exploited?

Yes. CVE-2025-20352 is listed in the CISA Known Exploited Vulnerabilities (KEV) catalog, added on September 29, 2025.

What is the CVSS score for CVE-2025-20352?

CVE-2025-20352 has a CVSS 3.1 base score of 7.7 (HIGH).

CVE-2025-20352

HIGH · CVSS 7.7CISA KEV: actively exploitedEPSS 40.2%EU EUVD: exploited

A vulnerability in the Simple Network Management Protocol (SNMP) subsystem of Cisco IOS Software and Cisco IOS XE Software could allow the following: An authenticated, remote attacker with low privileges could cause a denial of service (DoS) condition on an affected device that is running Cisco IOS Software or Cisco IOS XE Software. To cause the DoS, the attacker must have the SNMPv2c or earlier read-only community string or valid SNMPv3 user credentials. An authenticated, remote attacker with high privileges could execute code as the root user on an affected device that is running Cisco IOS XE Software. To execute code as the root user, the attacker must have the SNMPv1 or v2c read-only community string or valid SNMPv3 user credentials and administrative or privilege 15 credentials on the affected device. An attacker could exploit this vulnerability by sending a crafted SNMP packet to an affected device over IPv4 or IPv6 networks. This vulnerability is due to a stack overflow condition in the SNMP subsystem of the affected software. A successful exploit could allow a low-privileged attacker to cause the affected system to reload, resulting in a DoS condition, or allow a high-privileged attacker to execute arbitrary code as the root user and obtain full control of the affected system. Note: This vulnerability affects all versions of SNMP.

Key facts

CVSS score: 7.7 (v3.1)
Severity: HIGH
CVSS vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H
Weakness (CWE): CWE-121
EPSS score: 40.2% (99th percentile)
In CISA KEV: Yes, added September 29, 2025
In EU EUVD: Yes (EUVD-2025-31023)
Published: September 24, 2025
NVD last modified: September 26, 2026
Status: Analyzed

CISA Known Exploited Vulnerability

Cisco IOS and IOS XE Software SNMP Denial of Service and Remote Code Execution Vulnerability

Added to the KEV catalog on September 29, 2025; federal remediation due October 20, 2025.

EU Vulnerability Database (EUVD)

This vulnerability is also tracked by ENISA as EUVD-2025-31023 in the EU Vulnerability Database. ENISA flags it as known exploited. Last updated in EUVD on February 26, 2026.

View on the EU Vulnerability Database

Affected products

cisco / ios
cisco / ios
cisco / ios
cisco / ios
cisco / ios
cisco / ios
cisco / ios
cisco / ios
cisco / ios
cisco / ios
cisco / ios
cisco / ios
cisco / ios
cisco / ios
cisco / ios
cisco / ios
cisco / ios
cisco / ios
cisco / ios
cisco / ios
cisco / ios
cisco / ios
cisco / ios
cisco / ios
cisco / ios
cisco / ios
cisco / ios
cisco / ios
cisco / ios
cisco / ios
cisco / ios
cisco / ios
cisco / ios
cisco / ios
cisco / ios
cisco / ios
cisco / ios
cisco / ios
cisco / ios
cisco / ios
cisco / ios
cisco / ios
cisco / ios
cisco / ios
cisco / ios
cisco / ios
cisco / ios
cisco / ios
cisco / ios
cisco / ios

and 950 more…

Certified products that may be affected

15 FIPS 140 or Common Criteria certified products, from automated matching by sec-certs.org.

Cisco Embedded Services 9300 and 3300 Series Switches (ESS9300 & ESS3300) running IOS-XE 17.15 - Cisco Systems, Inc. - Common Criteria CCEVS-VR-VID-11662-2026 - active
Cisco Catalyst 8000V Edge (C8000V) running IOS-XE 17.15 - Cisco Systems, Inc. - Common Criteria Certificate Number: 2025/161 - active
Cisco 1000 Series Integrated Services Routers (C1100), Cisco Catalyst IR1800 Rugged Series Routers (IR1800), Cisco Catalyst IR8300 Rugged Series Routers (IR8300) running IOS-XE 17.15 - Cisco Systems, Inc. - Common Criteria CCEVS-VR-VID-11643-2025 - active
Cisco Catalyst Industrial Ethernet 9300 Rugged Series Switches running IOS-XE 17.15 - Cisco Systems, Inc. - Common Criteria CCEVS-VR-VID-11603-2025 - active
Cisco Aggregation Services Router 1000 Series (ASR1K), Cisco Catalyst 8200, 8300, 8500 Series Edge Routers (Cat8K) running IOS-XE version 17.15 - Cisco Systems, Inc. - Common Criteria CCEVS-VR-VID-11642-2025 - active

See all 15 in the Security Certifications Explorer.

References

https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-snmp-x4LPhte(Mitigation, Vendor Advisory)
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-20352(US Government Resource)

Last updated September 27, 2026 · Source: NVD, CISA KEV, FIRST.org EPSS

Query CVEs from your AI assistant

The CVE/NVD Explorer brain answers CVE questions directly inside Claude, ChatGPT, or any MCP assistant — always up to date, no setup. Add it once and stop pasting advisories into chat.

Add the CVE brain