WordPress core

CVE-2020-36326

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…

Severity: Critical 9.8
Published: 28 Apr 2021
Last changed: 17 Jun 2026
Added to UpHeron: 17 Oct 2026
Fixed in: 5.2.11, 5.3.8, 5.4.6, 5.5.5, 5.6.4, 5.7.2
Sources: NVD

Affected software

Software Affected versions

Software	Affected versions
WordPressWordPress core · `cpe:a:wordpress:wordpress`	From 5.7 before 5.7.2 From 5.6 before 5.6.4 From 5.5 before 5.5.5 From 5.4 before 5.4.6 All 21 release lines From 3.7 before 3.7.36 From 3.8 before 3.8.36 From 3.9 before 3.9.34 From 4.0 before 4.0.33 From 4.1 before 4.1.33 From 4.2 before 4.2.30 From 4.3 before 4.3.26 From 4.4 before 4.4.25 From 4.5 before 4.5.24 From 4.6 before 4.6.21 From 4.7 before 4.7.21 From 4.8 before 4.8.17 From 4.9 before 4.9.18 From 5.0 before 5.0.13 From 5.1 before 5.1.10 From 5.2 before 5.2.11 From 5.3 before 5.3.8 From 5.4 before 5.4.6 From 5.5 before 5.5.5 From 5.6 before 5.6.4 From 5.7 before 5.7.2

WordPressWordPress core · cpe:a:wordpress:wordpress

From 5.7 before 5.7.2
From 5.6 before 5.6.4
From 5.5 before 5.5.5
From 5.4 before 5.4.6

All 21 release lines

From 3.7 before 3.7.36
From 3.8 before 3.8.36
From 3.9 before 3.9.34
From 4.0 before 4.0.33
From 4.1 before 4.1.33
From 4.2 before 4.2.30
From 4.3 before 4.3.26
From 4.4 before 4.4.25
From 4.5 before 4.5.24
From 4.6 before 4.6.21
From 4.7 before 4.7.21
From 4.8 before 4.8.17
From 4.9 before 4.9.18
From 5.0 before 5.0.13
From 5.1 before 5.1.10
From 5.2 before 5.2.11
From 5.3 before 5.3.8
From 5.4 before 5.4.6
From 5.5 before 5.5.5
From 5.6 before 5.6.4
From 5.7 before 5.7.2

References

NVD https://nvd.nist.gov/vuln/detail/CVE-2020-36326
CVE.org https://www.cve.org/CVERecord?id=CVE-2020-36326