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TI-2019-01526 Aliases CVE-2019-1905GHSA-q65g-mrgj-hv5j

Cisco Email Security Appliance GZIP Content Filter Bypass Vulnerability

Priority LOW 35CWE-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 3.0 · CNA. Fix status from CNA.

Summary

A vulnerability in the GZIP decompression engine 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 validation of GZIP-formatted files. An attacker could exploit this vulnerability by sending a malicious file inside a crafted GZIP-compressed file. A successful exploit could allow the attacker to bypass configured content filters that would normally drop the email.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.01387 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—No fix listedCNA
  • Cisco Email Security Appliance (ESA) VendorCisco Affected 12.0 Fixed in — No fix listed CNA

CPE configurations NVD · 2

CPEVersionsRoleVendor
cpe:2.3:a:cisco:email_security_appliance:11.1.2:*:*:*:*:*:*:*11.1.2VulnerableCisco
cpe:2.3:a:cisco:email_security_appliance:12.0.0:*:*:*:*:*:*:*12.0.0VulnerableCisco
  • cpe:2.3:a:cisco:email_security_appliance:11.1.2:*:*:*:*:*:*:* Versions 11.1.2 Vulnerable ·Cisco
  • cpe:2.3:a:cisco:email_security_appliance:12.0.0:*:*:*:*:*:*:* Versions 12.0.0 Vulnerable ·Cisco

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2019-1905
  2. 2026-10-03 Alias added: GHSA-q65g-mrgj-hv5j

References

Advisory 1

  • 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-2019-01541 Cisco Email Security Appliance Content Filter Bypass Vulnerability CVSS 3.0HIGH 7.5
  • TI-2019-01553 Cisco Email Security Appliance Content Filter Bypass Vulnerability CVSS 3.0HIGH 7.4
See all 49 →

Sources

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