Cisco IOS and IOS XE Software SNMP Denial of Service and Remote Code Execution Vulnerability
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.
- Vendor
- Cisco
- Product
- IOS and IOS XE
- CVSS
- 7.7
- EPSS (exploit probability)
- 40.6%
- Status
- kev
- CISA patch-by (BOD 22-01)
- Added to KEV
Is CVE-2025-20352 being exploited?
Yes. CISA added CVE-2025-20352 to its Known Exploited Vulnerabilities catalog on . CISA only lists a CVE when it has reliable evidence of exploitation in the wild.
FIRST's EPSS model puts the probability of exploitation activity in the next 30 days at 40.6% (scored November 2, 2026).
- CISA KEV[ LISTED ]
- ENISA EUVD (exploited)[ — ]
- CIRCL KEV[ — ]
Catalog snapshot 2026-11-13. Full cross-catalog view: /kev-comparison
CVE-2025-20352 timeline
Every event links to its source. Catalog dates are each catalog's own; day offsets count from NVD publication. Data: JSON
What to do
CISA required actionApply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
US federal civilian agencies must remediate by (21 days after listing) under BOD 22-01. Everyone else: that deadline is a sensible upper bound, not a target. Vendor guidance and the NVD record are linked under Source above.
Other Cisco IOS and IOS XE CVEs we track
| CVE / Vulnerability | Severity | CVSS | EPSS | Added to KEV |
|---|---|---|---|---|
| CVE-2023-20109 Cisco IOS and IOS XE Group Encrypted Transport VPN Out-of-Bounds Write Vulnerability | [ MEDIUM ] | 6.6 | 2.5% | |
| CVE-2017-6742 Cisco IOS and IOS XE Software SNMP Remote Code Execution Vulnerability | [ HIGH ] | 8.8 | 21.3% | |
| CVE-2017-3881 Cisco IOS and IOS XE Remote Code Execution Vulnerability | [ CRITICAL ] | 9.8 | 99.0% | |
| CVE-2018-0173 Cisco IOS and IOS XE Software Improper Input Validation Vulnerability | [ HIGH ] | 8.6 | 7.6% | |
| CVE-2018-0172 Cisco IOS and IOS XE Software Improper Input Validation Vulnerability | [ HIGH ] | 8.6 | 7.8% | |
| CVE-2018-0159 Cisco IOS and XE Software Internet Key Exchange Version 1 Denial-of-Service Vulnerability | [ HIGH ] | 7.5 | 6.9% | |
| CVE-2018-0158 Cisco IOS and XE Software Internet Key Exchange Memory Leak Vulnerability | [ HIGH ] | 8.6 | 7.2% | |
| CVE-2018-0156 Cisco IOS Software and Cisco IOS XE Software Smart Install Denial-of-Service Vulnerability | [ HIGH ] | 7.5 | 9.4% |