CVE-2026-20304: 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.

criticalCVSS 9.9CVE-2026-20304

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 a software hardening release that address multiple internally discovered vulnerabilities. The vulnerabilities tracked by CVE-2026-20304 are related to improper access control issues that are grouped under the Common Weakness Enumeration (CWE) CWE-284.

Details

Source: NVD Recent CVEs (US · database · site)
Severity: critical — CVSS 9.9
Published: 2026-08-05
Last updated: 2026-08-06
Exploitation: Not in CISA KEV at last sync

Original advisory: https://nvd.nist.gov/vuln/detail/CVE-2026-20304

Exploitation outlook

EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.

Low exploitation riskCVE-2026-203040.25% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 17% of all EPSS-scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-20304	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.

high[NEW] [high] Cisco Catalyst SD-WAN Manager: Multiple Vulnerabilitiescert-bund
unknownNCSC-2026-0277 [1.00] [M/H] Vulnerabilities patched in Cisco Catalyst SD-WANncsc-nl
unknownMultiple vulnerabilities in Cisco products (August 6, 2026)cert-fr-avis
criticalCisco Advance Notification for Publication of August 5, 2026, Security Advisoriescisco-psirt
criticalCisco Catalyst SD-WAN Software Security Hardening Release: August 2026cisco-psirt

Recent advisories for As part of

A cluster of recent advisories against the same product widens the attack surface — attackers routinely chain freshly published CVEs on one product, so review these together.

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