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. 8 public proof-of-concept repositories are indexed.

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 servic…

Vulnerability class: Buffer Overflow

EPSS: 0.376 (98.4th 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 15.2\(4\)ea6, 15.6\(2\)sp7, 12.2(33)SXI13
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)

CWE-121 — Stack-based Buffer Overflow

CISA KEV (Known Exploited Vulnerabilities)

This CVE is on the CISA KEV catalog, added on 2025-09-29. 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: 2025-10-20.

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. 8 public proof-of-concept repositories are indexed.