CVE-2019-1955 - CVE House
Back to Database
Status published Medium CVE-2019-1955

Cisco Email Security Appliance Header Injection Vulnerability

Vulnerability Description

A vulnerability in the Sender Policy Framework (SPF) functionality of Cisco AsyncOS Software for Cisco Email Security Appliances (ESA) could allow an unauthenticated, remote attacker to bypass configured user filters on the device. The vulnerability is due to incomplete input and validation checking mechanisms for certain SPF messages that are sent to an affected device. An attacker could exploit this vulnerability by sending a customized SPF packet to an affected device. A successful exploit could allow the attacker to bypass the header filters that are configured for the affected device, which could allow malicious content to pass through the device.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

THREAT MONITOR

Am I Vulnerable?

Launch our assessment wizard to check if your infrastructure is exposed to • CVE-2019-1955

Credits & Attribution

No credits recorded in the NVD database.

References

More from Cisco

View All →
CVE-2025-20393
Cisco Secure Email Gateway and Cisco Secure Email and Web Manager Remote Command Execution Vulnerability
Critical 10
CVE-2025-20377
Cisco Unified Intelligence Center API Information Disclosure Vulnerability
Medium 4.3
CVE-2025-20376
Cisco Unified Contact Center Express Remote Code Execution Vulnerability
Medium 6.5
CVE-2025-20375
Cisco Unified Contact Center Express Arbitrary File Upload Vulnerability
Medium 6.5
CVE-2025-20374
Cisco Unified Contact Center Express Arbitrary File Download Vulnerability
Medium 4.9

Affected Vendor

Affected Software

Cisco Email Security Appliance (ESA)
Vulnerable Versions:
unspecified

Timeline

Official Publish: August 8th, 2019
Last Modified: November 19th, 2024
Added to House: July 20th, 2026

CVSS Vectors

V3: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

Weaknesses (CWE)

CWE-20

MITRE ATT&CK TTPs

T1190 Exploit Public-Facing Application
Initial Access
T1059 Command and Scripting Interpreter
Execution
T1068 Exploitation for Privilege Escalation
Privilege Escalation
T1213 Data from Information Repositories
Collection
T1565.002 Stored Data Manipulation
Impact