Cisco IOS XE up to 17.17.1 SNMP infinite loop

CVSS Meta Temp Score
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CTI Interest Score
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6.9$0-$5k0.00

Summaryinfo

A vulnerability was found in Cisco IOS XE. It has been classified as problematic. This vulnerability affects unknown code of the component SNMP. The manipulation leads to infinite loop. This vulnerability is uniquely identified as CVE-2025-20312. The attack is possible to be carried out remotely. No exploit exists. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability, which was classified as critical, has been found in Cisco IOS XE. This issue affects an unknown code block of the component SNMP. The manipulation with an unknown input leads to a infinite loop vulnerability. Using CWE to declare the problem leads to CWE-835. The product contains an iteration or loop with an exit condition that cannot be reached, i.e., an infinite loop. Impacted is availability. The summary by CVE is:

A vulnerability in the Simple Network Management Protocol (SNMP) subsystem of Cisco IOS XE Software could allow an authenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to improper error handling when parsing a specific SNMP request. An attacker could exploit this vulnerability by sending a specific 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 SNMPv2c 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 SNMPv3, the attacker must have valid SNMP user credentials for the affected system.

The advisory is shared at sec.cloudapps.cisco.com. The identification of this vulnerability is CVE-2025-20312 since 10/10/2024. The exploitation is known to be easy. The attack may be initiated remotely. Neither technical details nor an exploit are publicly available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 10/28/2025). MITRE ATT&CK project uses the attack technique T1499 for this issue.

The vulnerability scanner Nessus provides a plugin with the ID 271804 (Cisco IOS XE Software Simple Network Management Protocol DoS (cisco-sa-snmpwred-x3MJyf5M)), 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 (271804). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

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Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.1
VulDB Meta Temp Score: 6.9

VulDB Base Score: 6.5
VulDB Temp Score: 6.2
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 7.7
CNA Vector (cisco): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Infinite loop
CWE: CWE-835 / CWE-404
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 271804
Nessus Name: Cisco IOS XE Software Simple Network Management Protocol DoS (cisco-sa-snmpwred-x3MJyf5M)

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Timelineinfo

10/10/2024 CVE reserved
09/24/2025 +349 days Advisory disclosed
09/24/2025 +0 days VulDB entry created
10/28/2025 +34 days VulDB entry last update

Sourcesinfo

Vendor: cisco.com

Advisory: cisco-sa-snmpwred-x3MJyf5M
Status: Confirmed

CVE: CVE-2025-20312 (🔒)
GCVE (CVE): GCVE-0-2025-20312
GCVE (VulDB): GCVE-100-325757
scip Labs: https://www.scip.ch/en/?labs.20150108

Entryinfo

Created: 09/24/2025 19:27
Updated: 10/28/2025 23:00
Changes: 09/24/2025 19:27 (65), 10/28/2025 23:00 (2)
Complete: 🔍
Cache ID: 216::103

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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