Description
As part of Cisco's ongoing commitment to proactive security and product quality, the Cisco Catalyst SD-WAN engineering team has conducted a comprehensive internal security review. This review resulted in software hardening releases that address multiple internally discovered vulnerabilities.
The vulnerabilities tracked by CVE-2026-20303 are related to improper input validation issues that are grouped under the Common Weakness Enumeration (CWE) CWE-20.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Cisco | Cisco Catalyst SD-WAN Controller | 20.6.4, 20.9.2, 20.3.6, 20.7.2, 20.7.1, 20.5.1, 20.6.2, 19.3.0, 20.6.1, 17.2.4, 18.2.0, 18.4.6, 19.1.0, 19.2.4, 19.2.929, 18.3.8, 18.4.303, 18.3.7, 18.4.1, 19.2.097, 19.2.0, 19.2.099, 18.3.6, 20.4.2, 19.0.0, 20.9.1, 20.3.5, 20.3.1, 18.3.5, 20.6.3, 18.4.3, 18.4.4, 18.3.3, 17.2.8, 20.8.1, 19.2.32, 19… | — |
| 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, 17.2.9, 18.3.4, 17.2.5, 18.3.1.1, 18.3.5… | — |
Public exploits
Exploit or proof-of-concept code for this vulnerability is publicly available, which lowers the bar for attackers. Treat it as a reason to patch sooner.
GitHub 1 repository
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HORKimhab/Cisco-CVE-2026-20303-More ★ 0 · Aug 27, 2026
CVE-2026-20303, CVE-2026-20304, CVE-2026-20310, CVE-2026-20312, CVE-2026-20313
Sources: PoC-in-GitHub, Metasploit Framework, Exploit-DB — updated daily. Only links are listed; no exploit code is hosted here.
Advisories 2
- NCSC-2026-0277 Kwetsbaarheden verholpen in Cisco Catalyst SD-WAN NCSC-NL (Netherlands) · Aug 6, 2026
- WID-SEC-2026-2676 Cisco Catalyst SD-WAN Manager: Mehrere Schwachstellen BSI CERT-Bund (WID) · Aug 5, 2026