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TI-2019-01541 Aliases CVE-2019-1921GHSA-q86h-wvjc-7wh4

Cisco Email Security Appliance Content Filter Bypass Vulnerability

Priority MEDIUM 42CWE-20Published · Updated

Key facts

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

Attack profile from CVSS 3.0 · NVD. Fix status from CNA.

Summary

A vulnerability in the attachment scanning of Cisco AsyncOS Software for Cisco Email Security Appliance (ESA) could allow an unauthenticated, remote attacker to bypass configured content filters on the device. The vulnerability is due to improper input validation of the email body. An attacker could exploit this vulnerability by naming a malicious attachment with a specific pattern. A successful exploit could allow the attacker to bypass configured content filters that would normally block the attachment.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.01413 72nd 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)12.0.0-419—No fix listedCNA
  • Cisco Email Security Appliance (ESA) VendorCisco Affected 12.0.0-419 Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:cisco:email_security_appliance:12.0.0-419:*:*:*:*:*:*:*12.0.0-419VulnerableCisco
  • cpe:2.3:a:cisco:email_security_appliance:12.0.0-419:*:*:*:*:*:*:* Versions 12.0.0-419 Vulnerable ·Cisco

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2019-1921
  2. 2026-10-03 Alias added: GHSA-q86h-wvjc-7wh4

References

  • TI-2022-05357 Cisco Email Security Appliance and Cisco Secure Email and Web Manager External Authentication Bypass Vulnerability CVSS 3.1CRITICAL 9.8
  • TI-2019-01567 Cisco Email Security Appliance Denial of Service Vulnerability CVSS 3.1HIGH 8.6
  • TI-2018-00378 Improper input validation in Cisco Email Security Appliance CVSS 3.0HIGH 7.5
  • TI-2020-02695 Cisco Email Security Appliance Content Filter Bypass Vulnerability CVSS 3.1HIGH 7.5
  • TI-2019-01553 Cisco Email Security Appliance Content Filter Bypass Vulnerability CVSS 3.0HIGH 7.4
  • TI-2020-03092 Cisco Email Security Appliance Denial Of Service Vulnerability CVSS 3.1HIGH 7.5
See all 49 →

Sources