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TI-2018-11020 Aliases CVE-2018-15460GHSA-q66v-34fh-vw9m

Cisco Email Security Appliance URL Filtering Denial of Service Vulnerability

Priority MEDIUM 48CWE-20Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
No fix listed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-770.

Summary

A vulnerability in the email message filtering feature of Cisco AsyncOS Software for Cisco Email Security Appliances (ESA) could allow an unauthenticated, remote attacker to cause the CPU utilization to increase to 100 percent, causing a denial of service (DoS) condition on an affected device. The vulnerability is due to improper filtering of email messages that contain references to whitelisted URLs. An attacker could exploit this vulnerability by sending a malicious email message that contains a large number of whitelisted URLs. A successful exploit could allow the attacker to cause a sustained DoS condition that could force the affected device to stop scanning and forwarding email messages.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.02516 84th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
CiscoCisco Email Security Appliance (ESA)all versions—No fix listedCNA
  • Cisco Email Security Appliance (ESA) VendorCisco Affected all versions Fixed in — No fix listed CNA

CPE configurations NVD · 2

CPEVersionsRoleVendor
cpe:2.3:o:cisco:asyncos:*:*:*:*:*:*:*:*before 11.0.2-044_md; 11.1.0 to before 11.1.2-023_mdVulnerableCisco
cpe:2.3:h:cisco:email_security_appliance:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
  • cpe:2.3:o:cisco:asyncos:*:*:*:*:*:*:*:* Versions before 11.0.2-044_md; 11.1.0 to before 11.1.2-023_md Vulnerable ·Cisco
  • cpe:2.3:h:cisco:email_security_appliance:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2018-15460
  2. 2026-10-03 Alias added: GHSA-q66v-34fh-vw9m

References

Advisory 1

  • TI-2026-74174 Arbitrary file write in Cisco Secure Email Gateway via AMP feature KEVCVSS 3.1CRITICAL 9.8
  • TI-2026-53489 Cisco Secure Email Gateway SQL Injection Vulnerability KEVCVSS 3.1CRITICAL 9.8
  • TI-2025-14683 Cisco Secure Email Gateway and Cisco Secure Email and Web Manager Remote Command Execution Vulnerability KEVCVSS 3.1CRITICAL 10.0
  • TI-2021-13698 Cisco Web Security Appliance Proxy Service Denial of Service Vulnerability CVSS 3.1HIGH 8.6
  • TI-2019-01567 Cisco Email Security Appliance Denial of Service Vulnerability CVSS 3.1HIGH 8.6
  • TI-2019-01508 Cisco Web Security Appliance HTTPS Certificate Denial of Service Vulnerability CVSS 3.1HIGH 8.6
See all 55 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences