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TI-2019-09501 Aliases CVE-2019-12706GHSA-4xfr-4873-x36j

Cisco Email Security Appliance Filter Bypass Vulnerability

Priority MEDIUM 41CWE-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 3.1 · NVD. Fix status from CNA.

Summary

A vulnerability in the Sender Policy Framework (SPF) functionality of Cisco AsyncOS Software for Cisco Email Security Appliance (ESA) could allow an unauthenticated, remote attacker to bypass the configured user filters on an affected device. The vulnerability exists because the affected software insufficiently validates certain incoming SPF messages. An attacker could exploit this vulnerability by sending a custom SPF packet to an affected device. A successful exploit could allow the attacker to bypass the configured header filters, which could allow malicious content to pass through the device.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.01306 70th 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:*:*:*:*:*:*:*:*before 13.5.0VulnerableCisco
  • cpe:2.3:o:cisco:email_security_appliance_firmware:*:*:*:*:*:*:*:* Versions before 13.5.0 Vulnerable ·Cisco

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2019-12706
  2. 2026-10-03 Alias added: GHSA-4xfr-4873-x36j

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-2017-04429 Improper input validation in Cisco Email Security Appliance CVSS 3.0HIGH 7.5
See all 26 →

Sources

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