Skip to content

CVE-2025-20352

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

7.7 HIGHActively exploited (CISA KEV)EPSS 39.4%
  1. Published24 Sept 2025
  2. Added to CISA KEV29 Sept 2025
  3. Remediation due20 Oct 2025
Actively exploited (CISA KEV)

Cisco IOS and IOS XE contains a stack-based buffer overflow vulnerability in the Simple Network Management Protocol (SNMP) subsystem that could allow for denial of service or remote code execution. 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.

Added to KEV: 29 Sept 2025Federal remediation due: 20 Oct 2025

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.

CVSS 3.1 breakdown

Attack vectorNetwork
Attack complexityLow
Privileges requiredLow
User interactionNone
ScopeChanged
ConfidentialityNone
IntegrityNone
AvailabilityHigh
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H

Affected products

Cisco iOS12.2\(33\)sxi · 12.2\(33\)sxi1 · 12.2\(33\)sxi10 · 12.2\(33\)sxi11

Remediation

No fixed version is recorded in the NVD data. Check the vendor advisory for the latest guidance.

Frequently asked

Is CVE-2025-20352 being actively exploited?

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

How severe is CVE-2025-20352?

CVE-2025-20352 has a CVSS 3.1 base score of 7.7, rated high. EPSS estimates a 39.4% probability of exploitation.

Which products are affected by CVE-2025-20352?

Affected products include Cisco iOS.

How do I fix CVE-2025-20352?

Apply the vendor's patch or advisory guidance, then verify no affected versions remain across your devices.

How Secuno handles this

Secuno correlates vulnerabilities like CVE-2025-20352 against the real software inventory on every managed device, every day. Rather than a static severity, each match is scored in context: exploit availability, EPSS, the asset's exposure, and business criticality decide where it lands in the queue. Because it is on the CISA KEV list, Secuno flags any affected asset as top-priority automatically. If an affected version is present anywhere across your portfolio, it surfaces automatically with a prioritised remediation path.

Get Patch this first every Monday

Five vulnerabilities that matter this week, ranked on real exploitation. Plain language, one email, no spam.

You can unsubscribe with one click from every issue. We handle your details as described in our privacy policy.

Data from the NVD, CISA KEV catalog and FIRST EPSS. CVSS 3.1 base score shown where available.