CVE-2025-20352CiscoRouters and networkingSeptember 29, 2025

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

High 7.7Actively exploited

Description

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.

What to do

Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

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Details

Vendor
Cisco
Product
Cisco IOS e IOS XE
CVE
CVE-2025-20352
Affected versions
IOS 12.2: 73 versions, from 12.2(55)SE to 12.2(33)SXJ10
IOS 15.3: 79 versions, from 15.3(1)T to 15.3(3)JNP3
IOS 15.0: 65 versions, from 15.0(1)EY to 15.0(2)SQD8
IOS 15.1: 37 versions, from 15.1(1)SG to 15.1(2)SY16
IOS 15.2: 154 versions, from 15.2(4)M to 15.2(4)EA9a
IOS 15.4: 13 versions, from 15.4(1)T to 15.4(2)CG
IOS 15.5: 51 versions, from 15.5(1)S to 15.5(3)SN
IOS 15.6: 28 versions, from 15.6(1)S to 15.6(2)SP8
Cisco IOS XE Software 3.5: 13 versions, from 3.5.0E to 3.5.8SQ
Cisco IOS XE Software 3.6: 14 versions, from 3.6.0E to 3.6.10E
Cisco IOS XE Software 3.14: 5 versions, from 3.14.0S to 3.14.4S
Cisco IOS XE Software 3.15: 6 versions, from 3.15.0S to 3.15.4S
Cisco IOS XE Software 3.7: 6 versions, from 3.7.0E to 3.7.5E
Cisco IOS XE Software 3.16: 22 versions, from 3.16.0S to 3.16.10S
Cisco IOS XE Software 3.17: 6 versions, from 3.17.0S to 3.17.4S
Cisco IOS XE Software 3.8: 12 versions, from 3.8.0E to 3.8.10E
Cisco IOS XE Software 3.18: 22 versions, from 3.18.0aS to 3.18.9SP
Cisco IOS XE Software 3.9: 3.9.0E; 3.9.1E; 3.9.2E
Cisco IOS XE Software 16.6: 12 versions, from 16.6.1 to 16.6.10
Cisco IOS XE Software 16.7: 6 versions, from 16.7.1 to 16.7.4
Cisco IOS XE Software 16.8: 9 versions, from 16.8.1 to 16.8.3
Cisco IOS XE Software 16.9: 13 versions, from 16.9.1 to 16.9.8
Cisco IOS XE Software 16.10: 11 versions, from 16.10.1 to 16.10.3
Cisco IOS XE Software 3.10: 5 versions, from 3.10.0E to 3.10.3E
Cisco IOS XE Software 16.11: 5 versions, from 16.11.1 to 16.11.2
Cisco IOS XE Software 16.12: 31 versions, from 16.12.1 to 16.12.13
Cisco IOS XE Software 3.11: 15 versions, from 3.11.0E to 3.11.12E
Cisco IOS XE Software 17.1: 5 versions, from 17.1.1 to 17.1.3
Cisco IOS XE Software 17.2: 6 versions, from 17.2.1 to 17.2.3
Cisco IOS XE Software 17.3: 19 versions, from 17.3.1 to 17.3.8a (from the advisory and NVD; check the exact builds in the official advisory)
CVSS score
7.7
Actively exploited
Yes, listed in the CISA Known Exploited Vulnerabilities catalog
CISA due date
October 20, 2025 (deadline for US federal agencies: a good benchmark for you too)
Source
CISA KEV – original advisory
Published
September 29, 2025

The description and the recommended action are quoted from the public advisory; severity, exploitation status and affected versions are compiled automatically from public sources and may contain errors. The vendor's original advisory prevails: check it before taking action. This information is provided without warranty and does not replace a professional assessment.

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