Vulnerability record

CVE-2025-20352

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

Severity: HighExploitation: Exploitation confirmedCISA KEV
What should I do?

This vulnerability is in the CISA Known Exploited Vulnerabilities catalog: attackers are using it. If you run IOS and IOS XE, fix it now.

CISA 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.

US federal civilian agencies must remediate by Oct 20, 2025.

Patch status

No official fix confirmed yet

Until a fix ships, follow the vendor's mitigations and CISA's required action, limit exposure of affected systems, and watch this record for a patch.

Description

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.

Source: NIST National Vulnerability Database. Official vulnerability data, reproduced as published.

Affected products

Products affected by this vulnerability, with versions and the source of each entry
ProductVendorAffected versionsSource
Cisco networking & securityCisco3.5.0e; 3.5.0sq; 3.5.1e; 3.5.1sq; 3.5.2e; 3.5.2sqNVD
IOSCisco12.2\(33\)sxi; 12.2\(33\)sxi1; 12.2\(33\)sxi2; 12.2\(33\)sxi2a; 12.2\(33\)sxi3; 12.2\(33\)sxi4NVD
IOS and IOS XECisco—KEV

Sources: NVD = NIST National Vulnerability Database; KEV = CISA Known Exploited Vulnerabilities catalog.

Intelligence timeline

Developments from the last 30 days, newest first.

  1. CVSS scoredUpdateKEV

    CVE-2025-20352 scored CVSS 7.7: Cisco IOS and IOS XE, Cisco IOS and IOS XE Software SNMP Denial of Service and Remote Code Execution Vulnerability

    CISA lists this as exploited in the wild. Unpatched IOS and IOS XE systems are exposed to active attacks now.

    Basis: NIST National Vulnerability Database

1 earlier event is available with a subscription. See plans.

Coverage

We have not published a story about this vulnerability yet.

References

  • sec.cloudapps.cisco.com https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-snmp-x4LPhte
  • nvd.nist.gov https://nvd.nist.gov/vuln/detail/CVE-2025-20352
  • cisa.gov https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-20352