CVE-2025-20171
Published: 05 February 2025
Summary
CVE-2025-20171 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 46.6% 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 CM-7 (Least Functionality) and SI-11 (Error Handling).
Threat & Defense at a Glance
Threat & Defense Details
Mitigating Controls (NIST 800-53 r5)AI
Remediates the specific SNMP parsing flaw causing DoS by requiring timely application of vendor software updates.
Directly addresses improper error handling in SNMP request parsing to prevent uncaught exceptions that trigger device reloads.
Prohibits unnecessary SNMP functionality or versions like v1/v2c, eliminating the authenticated remote attack vector.
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
The CVE describes exploitation of an SNMP parsing flaw via crafted authenticated requests to trigger device reload and DoS, directly matching Application or System Exploitation under Endpoint DoS.
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-2025-20171 is a vulnerability in the SNMP subsystem of Cisco IOS Software and Cisco IOS XE Software that stems from improper error handling when parsing SNMP requests. It affects SNMP versions 1, 2c, and 3, with a CVSS v3.1 base score of 7.7 (AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H) and is associated with CWE-248 (Uncaught Exception). An authenticated, remote attacker could exploit this by sending a crafted SNMP request to an affected device, causing it to reload unexpectedly and triggering a denial-of-service (DoS) condition.
Exploitation requires authentication: for SNMP v2c or earlier, the attacker must know a valid read-write or read-only SNMP community string; for SNMP v3, valid SNMP user credentials are needed. A successful attack results solely in a DoS, with no impact on confidentiality or integrity, as the device scope is changed (S:C).
The Cisco Security Advisory at https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-snmp-dos-sdxnSUcW provides details on affected versions and mitigation steps, including software updates where available.
Details
- CWE(s)