CVE-2025-20173
Published: 05 February 2025
Summary
CVE-2025-20173 is a high-severity Uncaught Exception (CWE-248) vulnerability in Cisco Ios. Its CVSS base score is 7.7 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Application or System Exploitation (T1499.004); ranked in the top 23.6% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.
The strongest mitigations our analysis identified are NIST 800-53 SC-5 (Denial-of-service Protection) and SI-11 (Error Handling).
Threat & Defense at a Glance
Threat & Defense Details
Mitigating Controls (NIST 800-53 r5)AI
Flaw remediation directly addresses the vulnerability by applying vendor patches to fix the improper error handling in SNMP request parsing.
Error handling control ensures the system implements robust mechanisms to prevent crashes from malformed SNMP requests without compromising security.
Denial-of-service protection limits the effects of crafted SNMP requests that trigger device reloads and identifies such events.
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
Improper SNMP request parsing directly enables remote authenticated DoS via crafted packets that crash/reload the device, mapping to application/system exploitation for endpoint denial of service.
NVD Description
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…
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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.
Deeper analysisAI
CVE-2025-20173 is a vulnerability in the SNMP subsystem of Cisco IOS Software and Cisco IOS XE Software that stems from improper error handling during the parsing of SNMP requests. This flaw affects SNMP versions 1, 2c, and 3, enabling an authenticated, remote attacker to trigger a denial-of-service (DoS) condition by sending a crafted SNMP request, which causes the affected device to reload unexpectedly.
An attacker requires low privileges to exploit this vulnerability: for SNMP v2c or earlier, knowledge of a valid read-write or read-only community string; for SNMP v3, valid user credentials. Successful exploitation results in a scoped DoS, as indicated by the CVSS v3.1 base score of 7.7 (AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H), with no impact on confidentiality or integrity.
The Cisco Security Advisory provides further details on this issue, available at https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-snmp-dos-sdxnSUcW.
Details
- CWE(s)