CISCO Security Advisory
Published Date: Not specified
CVE: CVE-2026-20337
Advisory Summary
🗓️📅 August 13, 2026
🔷 🏷️ ClamAV Vulnerabilities Affecting Cisco Products — August 2026
🚨 ⚠️ Alarm: Remote DoS Risk Impacts Email/Malware Scanning Continuity
Cisco reports multiple ClamAV vulnerabilities that can be triggered remotely to cause denial of service (DoS), potentially interrupting scanning operations on affected Cisco endpoints/connectors. No compensating workarounds are provided—updates are the primary mitigation.
- Windows-based platforms (SIR: High): ClamAV scanning runs in a privileged security context.
- Highest impact called out: Cisco Secure Endpoint Connector for Windows
- Linux/Mac platforms (SIR: Medium): ClamAV runs in a lower-privileged context.
- Affected examples: Secure Endpoint Connector for Linux and Mac
- Cisco Secure Endpoint Private Cloud: Not impacted, but the Connector software distributed from the device is impacted.
🧾 🎯 CVEs referenced
CVE-2026-20337, CVE-2026-20338, CVE-2026-20339, CVE-2026-20345, CVE-2026-20346, CVE-2026-20347, CVE-2026-20348
🛡️ ✅ Market-actionable steps (do now)
1. Identify affected connector deployments (Windows, Linux, macOS) and inventory versions of Cisco Secure Endpoint Connector components.
2. Prioritize Windows updates first due to High SIR and privileged execution context.
3. Apply Cisco software updates referenced in the advisory—since no workarounds exist.
4. Validate scanning continuity post-patch (monitor scanning job status, error rates, queue backlogs, and alerting signals).
5. Harden exposure paths where applicable (reduce inbound reachability that could trigger remote conditions, and ensure only intended network paths can submit scan workloads).
⚠️ 🔐 Security posture note
Even when impact is “just” DoS, disrupted scanning can create operational security gaps (delayed malware detection, quarantine delays, reduced protection coverage). Treat patching as availability + security control continuity.
-2026-20337
Reference: Vendor Advisory