GHSA-5f37-gxvh-23v6

### Impact
The `mailSend` function in the default `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.

### Patches
Fixed in 5.2.18

### Workarounds
Filter and validate user input before passing it to internal functions.

### References
https://nvd.nist.gov/vuln/detail/CVE-2016-10033
Related to a follow-on issue in https://nvd.nist.gov/vuln/detail/CVE-2016-10045

### For more information
If you have any questions or comments about this advisory:
* Open a private issue in [the PHPMailer project](https://github.com/PHPMailer/PHPMailer)