Cisco Publishes 12 Security Advisories Fixing Critical Flaws in Catalyst SD-WAN and IOS XE
Cisco Systems released 12 new security advisories on August 5, 2026, disclosing a total of 23 vulnerabilities across multiple products including Cisco Catalyst SD-WAN Software and Cisco IOS XE Software.
Two of the advisories were rated Critical, the highest severity level. The Cisco Catalyst SD-WAN Software advisory covers five vulnerabilities. The most severe include input validation issues tracked as CVE-2026-20303, access control bypass CVE-2026-20304, and link interpretation problems CVE-2026-20310, all carrying a CVSSv3.1 base score of 9.9.
The Cisco IOS XE Software advisory addresses seven flaws. Notable entries are improper neutralization of special elements CVE-2026-20272 (CVSS 9.8) and access control weaknesses CVE-2026-20267 (CVSS 9.0), plus five additional issues rated 8.6.
Further advisories cover argument injection in Cisco Integrated Management Controller, denial-of-service conditions in Extensible Messaging Client Protocol and SNMP implementations, information disclosure in Cisco Catalyst SD-WAN Manager and RoomOS, and firewall rule bypass in Cisco Terminal Services Agent.
Links to the full advisories and hardening releases are available on the Cisco security portal. Administrators should prioritize patching to prevent remote code execution and denial-of-service attacks.
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