Buffer overflow in Cisco iOS Xe Catalyst Sd-Wan
CVE-2025-20352
A vulnerability in the Simple Network Management Protocol (SNMP) subsystem of Cisco IOS Software and Cisco IOS XE Software could allow the following: An authenticated, remote attacker with low privileges could cause a denial of service (DoS) condition on an affected device that is running Cisco IOS Software or Cisco IOS XE Software. To cause the DoS, the attacker must have the SNMPv2c or earlier read-only community string or valid SNMPv3 user credentials. An authenticated, remote attacker with high privileges could execute code as the root user on an affected device that is running Cisco IOS XE Software. To execute code as the root user, the attacker must have the SNMPv1 or v2c read-only community string or valid SNMPv3 user credentials and administrative or privilege 15 credentials on the affected device. An attacker could exploit this vulnerability by sending a crafted SNMP packet to an affected device over IPv4 or IPv6 networks. This vulnerability is due to a stack overflow condition in the SNMP subsystem of the affected software. 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. Note: This vulnerability affects all versions of SNMP.
Vulnerability class: Buffer Overflow
EPSS: 0.394 (98.5th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 7.7 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H.
Affected products
- Cisco Ios Xe Catalyst Sd-wan — versions 16.9.1, 16.9.2, 16.9.3
- Cisco Ios Xe Software — versions 3.5.0E, 3.5.1E, 3.5.2E
- Cisco Ios — versions 15.6\(2\)sp7, 15.2(4)ec2, 15.2(4)jb1
- Cisco Ios_xe — versions 3.5.0e, 3.5.0sq, 3.5.1e
- Cisco Ios_xe_sd-wan — versions 16.9.1, 16.9.2, 16.9.3
Weakness classification (CWE)
CISA KEV (Known Exploited Vulnerabilities)
This CVE is on the CISA KEV catalog, added on . CISA KEV inclusion means CISA has confirmed in-the-wild exploitation; US federal agencies are required to remediate within a published due date.
BOD 22-01 due date: .
Required action: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Public proof-of-concept exploits
References
- psirt@cisco.com (Mitigation, Vendor Advisory)
- 134c704f-9b21-4f2e-91b3-4a467353bcc0 (US Government Resource)
Frequently asked questions
- What is CVE-2025-20352?
- CVE-2025-20352 is a high-severity vulnerability in Cisco iOS Xe Catalyst Sd-Wan, classified under Stack-based Buffer Overflow. CVSS score: 7.7/10. Published 2025-09-24.
- How severe is CVE-2025-20352?
- High severity. CVSS v3 base score is 7.7 out of 10.
- Is CVE-2025-20352 known to be exploited?
- Yes. CVE-2025-20352 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2025-09-29), indicating it is being actively exploited. 9 public proof-of-concept repositories are indexed.