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TI-2020-03112 Aliases CVE-2020-3568GHSA-p4j6-jcqv-hh27

Cisco Email Security Appliance URL Filtering Bypass Vulnerability

Priority LOW 34CWE-20Published · Updated

Key facts

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

Attack profile from CVSS 3.1 · CNA. Fix status from CNA.

Summary

A vulnerability in the antispam protection mechanisms of Cisco AsyncOS Software for Cisco Email Security Appliance (ESA) could allow an unauthenticated, remote attacker to bypass the URL reputation filters on an affected device. The vulnerability is due to insufficient input validation of URLs. An attacker could exploit this vulnerability by crafting a URL in a particular way. A successful exploit could allow the attacker to bypass the URL reputation filters that are configured for the affected device, which could allow malicious URLs to pass through the device.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.01002 63rd 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 · 1

CPEVersionsRoleVendor
cpe:2.3:o:cisco:asyncos:*:*:*:*:*:*:*:*up to 13.5.2VulnerableCisco
  • cpe:2.3:o:cisco:asyncos:*:*:*:*:*:*:*:* Versions up to 13.5.2 Vulnerable ·Cisco

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2020-3568
  2. 2026-10-03 Alias added: GHSA-p4j6-jcqv-hh27

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-2018-11020 Cisco Email Security Appliance URL Filtering 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
See all 55 →

Sources

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