CISCO Security Advisory
Published Date: Not specified
CVE: CVE-2026-20337
Advisory Summary
⬛ 🧩 ClamAV DoS Vulnerabilities Impacting Cisco Endpoint Connector Software (Aug 2026)
Cisco reports multiple ClamAV vulnerabilities that can be exploited by a remote attacker to trigger a Denial of Service (DoS) condition, interrupting or disrupting antivirus scanning operations. Cisco indicates no workarounds are available; targeted software updates will be released for affected platforms.
⚠️ 🚨 Key Takeaways for Market & Security Teams
◆ High impact on Windows connectors: Higher Security Impact Rating (SIR) applies because the ClamAV scanning process runs in a privileged security context on Windows.
◆ Medium impact on Linux/Mac connectors: Lower privileged execution reduces impact severity (but scanning availability can still be disrupted).
◆ Cisco Secure Endpoint Private Cloud not directly impacted: The vulnerability affects the Connector software distributed from the device, not the private cloud service itself.
⛏️ 🔎 Affected Product Scope (as stated)
● High (Windows): Cisco Secure Endpoint Connector for Windows (notably Cisco Secure Endpoint Connector for Windows)
● Medium (Linux/Mac): Cisco Secure Endpoint Connector for Linux and Mac
🧾 🧨 Vulnerabilities Identified
CVE list: CVE-2026-20337, CVE-2026-20338, CVE-2026-20339, CVE-2026-20345, CVE-2026-20346, CVE-2026-20347, CVE-2026-20348
🛡️ ✅ Recommended Actions (Actionable)
Informations:
1) Inventory all deployments of Secure Endpoint Connector across Windows/Linux/Mac and confirm versions in use.
2) Prioritize Windows remediation first due to the High SIR context.
3) Implement a patch/upgrade workflow aligned to Cisco’s forthcoming releases; verify connector package integrity after update.
4) Add temporary operational guardrails: monitor for scanning process failures/timeouts and alert on AV scan interruptions until fully patched.
- If exploitation leads to scanning disruption, endpoint malware detection coverage may degrade, creating indirect breach risk (attackers seek evasion windows).
- Even where SIR is “Medium” (Linux/Mac), availability of scanning remains a business-critical function.
-2026
Reference: Vendor Advisory