CVE-2016-10033
CriticalActively exploited (CISA KEV)
Description
The mailSend function in the isMail transport in PHPMailer before 5.2.18 might allow remote attackers to pass extra parameters to the mail command and consequently execute arbitrary code via a \" (backslash double quote) in a crafted Sender property.
SeverityCritical
CVSS9.8
Exploit probability100. percentile99.7%
Product
PHPMailer
PublishedDec 30, 2016
First seenDec 30, 2016
Added to KEVJul 7, 2025
Weakness typeCWE-88CWE-88
How to fix
CISA required action
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
CISA due date: Jul 28, 2025Update
- phpmailer_project phpmailer5.2.18 or later
- phpmailer/phpmailer5.2.18 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| phpmailer_project phpmailer | v < 5.2.18 | 5.2.18 |
| wordpress wordpress | v ≤ 4.7 | — |
| joomla joomla\! | 1.5.0 ≤ v ≤ 3.6.5 | — |
| phpmailer/phpmailerPackagist | 5.0.0 ≤ v < 5.2.18 | 5.2.18 |
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