Cisco IOS/IOS XE Software SNMP Subsystem buffer access with incorrect length value

Summaryinfo

A vulnerability was found in Cisco IOS and IOS XE Software and classified as critical. Affected by this issue is some unknown functionality of the component SNMP Subsystem. Such manipulation leads to buffer access with incorrect length value. This vulnerability is documented as CVE-2025-20169. The attack can be executed remotely. There is not any exploit available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability was found in Cisco IOS and IOS XE Software (the affected version is unknown) and classified as critical. Affected by this issue is an unknown code of the component SNMP Subsystem. The manipulation with an unknown input leads to a buffer access with incorrect length value vulnerability. Using CWE to declare the problem leads to CWE-805. The product uses a sequential operation to read or write a buffer, but it uses an incorrect length value that causes it to access memory that is outside of the bounds of the buffer. Impacted is availability. CVE summarizes:

A vulnerability in the SNMP subsystem of Cisco IOS Software and Cisco IOS XE Software could allow an authenticated, remote attacker to cause a DoS condition on an affected device. This vulnerability is due to improper error handling when parsing SNMP requests. An attacker could exploit this vulnerability by sending a crafted SNMP request to an affected device. A successful exploit could allow the attacker to cause the device to reload unexpectedly, resulting in a DoS condition.  This vulnerability affects SNMP versions 1, 2c, and 3. To exploit this vulnerability through SNMP v2c or earlier, the attacker must know a valid read-write or read-only SNMP community string for the affected system. To exploit this vulnerability through SNMP v3, the attacker must have valid SNMP user credentials for the affected system.

The advisory is available at sec.cloudapps.cisco.com. This vulnerability is handled as CVE-2025-20169 since 10/10/2024. The exploitation is known to be easy. The attack may be launched remotely. The technical details are unknown and an exploit is not available. The structure of the vulnerability defines a possible price range of USD $5k-$25k at the moment (estimation calculated on 10/31/2025).

The vulnerability scanner Nessus provides a plugin with the ID 215126 (Cisco IOS Software SNMP DoS (cisco-sa-snmp-dos-sdxnSUcW)), which helps to determine the existence of the flaw in a target environment.

Upgrading eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (215126). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Type

• Router Operating System

Vendor

• Cisco

Name

• IOS
• IOS XE Software

License

• commercial

Website

• Vendor: https://www.cisco.com/

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Entryinfo

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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