CVE-2026-76504
Cisco Catalyst SD-WAN Manager Hex Encoding Vulnerability
Cisco Catalyst SD-WAN Manager contains a hex encoding vulnerability that could allow an unauthenticated, remote attacker to access an affected system with privileges of the admin user due to improper handling of URI encoding in an HTTP request.
CISA due Oct 3, 2026
- Cisco Catalyst SD-WAN Manager
- Critical
- CVSS 9.8
- EPSS 1.82%
- No fixed version listed here
What to do
No fixed version listed here
- Required action
- Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable.
- CISA deadline for US federal agencies
- Oct 3, 2026
Affected products
| Product | Affected | Fixed in |
|---|---|---|
| Cisco Cisco Catalyst SD-WAN Manager | 20.1.12; 19.2.1; 18.4.4; 18.4.5; 20.1.1.1; 20.1.1; 19.3.0; 19.2.2; 19.2.099; 18.3.6; 18.3.7; 19.2.0; 18.3.8; 19.0.0; 19.1.0; 18.4.302; 18.4.303; 19.2.097; 19.2.098; 17.2.10; 18.3.6.1; 19.0.1a; 18.2.0; 18.4.3; 18.4.1; 17.2.8; 18.3.3.1; 18.4.0; 18.3.1; 17.2.6 | Only in the CVE record |
The CVE record lists 385 ranges this page cannot state exactly.
Scores and signals
- Exploitation
- Exploited in the wild
- Severity
- Critical, CVSS 9.8 (v3.1, scored by cisco)
- EPSS
- 1.82% chance of exploitation in the next 30 days (EPSS from FIRST, as of Oct 23, 2026)
- CISA's SSVC decision points
- Exploitation: active. Automatable: yes. Technical impact: total. As of Sep 30, 2026.
- Weakness
- CWE-177: Improper Handling of URL Encoding (Hex Encoding)
- Vendor
- Cisco, Catalyst SD-WAN Manager
Timeline
- Added to CISA's Known Exploited Vulnerabilities catalog: exploited in the wild. US federal agencies must remediate by 2026-10-03.