- Critical 9.8
- Known exploited (CISA KEV)
CVE-2026-76504
A vulnerability in the API session-based authentication management of Cisco Catalyst SD-WAN Manager could allow an unauthenticated, remote attacker to access an affected system with privileges of the admin user. This vulnerability is due to improper handling of URI encoding in an HTTP request, which allows the request to bypass an authentication rule that is intended to restrict access to a specific API endpoint. An attacker could exploit this vulnerability by sending a crafted HTTP request to the API of the affected system. A successful exploit could allow the attacker to bypass authenticati…
Scores
The facts
- Published
- 30 September 2026
- Last changed
- 3 October 2026
- NVD status
- Analyzed
- Severity
- Critical, CVSS 9.8 out of 10 (version 3.1)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Weakness
- Affects
- cisco catalyst sd-wan manager
- Known exploited
- Yes. CISA added it to the Known Exploited Vulnerabilities catalogue on 30 September 2026.
- EPSS
- 1.8% chance of exploitation activity in the next 30 days (percentile 78).
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