CVE-2020-36326

CRITICAL

PHPMailer 6.1.8-6.4.0 - Object Injection via addAttachment UNC Pathname

Title source: llm
STIX 2.1

Description

PHPMailer 6.1.8 through 6.4.0 allows object injection through Phar Deserialization via addAttachment with a UNC pathname. NOTE: this is similar to CVE-2018-19296, but arose because 6.1.8 fixed a functionality problem in which UNC pathnames were always considered unreadable by PHPMailer, even in safe contexts. As an unintended side effect, this fix eliminated the code that blocked addAttachment exploitation.

Scores

CVSS v3 9.8
EPSS 0.0030
EPSS Percentile 53.7%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Details

CWE
CWE-502
Status published
Products (3)
phpmailer/phpmailer 6.1.8 - 6.4.1Packagist
phpmailer_project/phpmailer 6.1.8 - 6.4.0
wordpress/wordpress 3.7 - 3.7.36
Published Apr 28, 2021
Tracked Since Feb 18, 2026