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TI-2019-12028 Aliases CVE-2019-15988GHSA-vxf2-rc93-x6wf

Cisco Email Security Appliance URL Filtering Bypass Vulnerability

Priority LOW 32CWE-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 · NVD. 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 the 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 0.01011 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:email_security_appliance_firmware:*:*:*:*:*:*:*:*up to 12.5.0VulnerableCisco
  • cpe:2.3:o:cisco:email_security_appliance_firmware:*:*:*:*:*:*:*:* Versions up to 12.5.0 Vulnerable ·Cisco

Remediation

No fixed version listed by the sources yet.

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Release ·

    Cisco Email Security Appliance (ESA) n/a

    2 records Highest priority Priority LOW 2 LOW

    Other records, highest priority first

    • TI-2019-12011 Cisco Email Security Appliance MP3 Content Filter Bypass VulnerabilityPriority LOW 26
    Show all 2 records →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2019-15988
  2. 2026-10-03 Alias added: GHSA-vxf2-rc93-x6wf

References

Advisory 1

  • TI-2018-11013 Cisco Email Security Appliance Memory Corruption Denial of Service Vulnerability CVSS 3.1HIGH 8.6
  • TI-2016-05488 Cisco IronPort AsyncOS 9.1.2-023, 9.1.2-028, 9.1.2-036, 9.7.2-046, 9.7.2-047, 9.7.2-054… CVSS 3.0CRITICAL 9.8
  • TI-2019-12004 Clam AntiVirus (ClamAV) Software Email Parsing Vulnerability CVSS 3.1HIGH 7.5
  • TI-2019-01575 Cisco Email Security Appliance Header Injection Vulnerability CVSS 3.1HIGH 7.5
  • TI-2014-01669 The End User Safelist/Blocklist (aka SLBL) service in Cisco AsyncOS Software for Email… CVSS 2.0HIGH 8.5
  • TI-2019-09501 Cisco Email Security Appliance Filter Bypass Vulnerability CVSS 3.1HIGH 7.5
See all 26 →

Sources

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