CVE-2020-36326

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.

How to fix CVE-2020-36326

To remediate CVE-2020-36326, upgrade the affected package to a fixed version below.

—upgrade to 6.4.1 or later
—upgrade to 3.7.36 or later
—upgrade to 3.7.36 or later
—upgrade to 6.2.0-2 or later
—upgrade to 6.4.1 or later

Is CVE-2020-36326 being exploited?

Low — EPSS is 0.3%, meaning exploitation activity has not been observed at scale.

Affected packages (5)

>= 6.1.8, < 6.4.1
>= 3.7.0, < 3.7.36, >= 3.8.0, < 3.8.36, >= 3.9.0, < 3.9.34, >= 4.0.0, < 4.0.33, >= 4.1.0, < 4.1.33, >= 4.2.0, < 4.2.30, >= 4.3.0, < 4.3.26, >= 4.4.0, < 4.4.25, >= 4.5.0, < 4.5.24, >= 4.6.0, < 4.6.21, >= 4.7.0, < 4.7.21, >= 4.8.0, < 4.8.17, >= 4.9.0, < 4.9.18, >= 5.0.0, < 5.0.13, >= 5.1.0, < 5.1.10, >= 5.2.0, < 5.2.11, >= 5.3.0, < 5.3.8, >= 5.4.0, < 5.4.6, >= 5.5.0, < 5.5.5, >= 5.6.0, < 5.6.4, >= 5.7.0, < 5.7.2
>= 3.7.0, < 3.7.36, >= 3.8.0, < 3.8.36, >= 3.9.0, < 3.9.34, >= 4.0.0, < 4.0.33, >= 4.1.0, < 4.1.33, >= 4.2.0, < 4.2.30, >= 4.3.0, < 4.3.26, >= 4.4.0, < 4.4.25, >= 4.5.0, < 4.5.24, >= 4.6.0, < 4.6.21, >= 4.7.0, < 4.7.21, >= 4.8.0, < 4.8.17, >= 4.9.0, < 4.9.18, >= 5.0.0, < 5.0.13, >= 5.1.0, < 5.1.10, >= 5.2.0, < 5.2.11, >= 5.3.0, < 5.3.8, >= 5.4.0, < 5.4.6, >= 5.5.0, < 5.5.5, >= 5.6.0, < 5.6.4, >= 5.7.0, < 5.7.2
from 0, < 6.2.0-2
>= 6.1.8, < 6.4.1

CVSS scores

Source	Version	Severity	Vector
osv	CVSS 3.1	CRITICAL9.8	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H