CVE-2026-121946
Published:November 04, 2026
Updated:November 12, 2026
zbateson mail-mime-parser before 3.0.9 and 4.x before 4.0.6 contains a CRLF header injection vulnerability in message-building helpers that fail to strip CR and LF characters. Attackers supplying crafted MIME type, charset, encoding, micalg, or protocol values can inject extra header lines such as a forged Bcc into outgoing messages.
Affected Packages
https://github.com/zbateson/mail-mime-parser.git (GITHUB):
Affected version(s) >=4.0.0 <4.0.6Fix Suggestion:
Update to version 4.0.6https://github.com/zbateson/mail-mime-parser.git (GITHUB):
Affected version(s) >=0.3.0 <3.0.9 || >=1.0-alpha <3.0.9 || >=2.0.0-beta <3.0.9 || >=3.0.0-beta <3.0.9Fix Suggestion:
Update to version 3.0.9zbateson/mail-mime-parser (PHP):
Affected version(s) >=4.0.0 <4.0.6Fix Suggestion:
Update to version 4.0.6zbateson/mail-mime-parser (PHP):
Affected version(s) >=2.0.0-beta <3.0.9 || >=1.0-alpha <3.0.9 || >=0.3.0 <3.0.9 || >=3.0.0-beta <3.0.9Fix Suggestion:
Update to version 3.0.9Related Resources (10)
Do you need more information?
Contact UsCVSS v4
Base Score:
6.9
Attack Vector
NETWORK
Attack Complexity
LOW
Attack Requirements
NONE
Privileges Required
NONE
User Interaction
NONE
Vulnerable System Confidentiality
LOW
Vulnerable System Integrity
LOW
Vulnerable System Availability
NONE
Subsequent System Confidentiality
LOW
Subsequent System Integrity
LOW
Subsequent System Availability
NONE
CVSS v3
Base Score:
7.2
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
CHANGED
Confidentiality
LOW
Integrity
LOW
Availability
NONE
Weakness Type (CWE)
Improper Neutralization of CRLF Sequences
EPSS
Base Score:
0.33