Phpmailer vulnerabilitiesAnd the versions its exploited flaws hit.
Phpmailer is made by Phpmailer Project. We track 10 published vulnerabilities in it, across 51 versions. 1 of them is on the list of flaws known to be exploited, the newest added on 7 July 2025. If you run Phpmailer, check your version against the exploited flaws below and patch those first.
The most recent Phpmailer flaw added to the known-exploited list is CVE-2016-10033, on 7 July 2025. We keep watching the known-exploited list.
Which versions of Phpmailer do the exploited flaws hit?
Each exploited flaw lists the versions it affects, usually as ranges. "before 5.2.18" means every version up to, but not including, 5.2.18. Find your version, then patch.
- CVE-2016-10033Exploited list, 7 Jul 2025
PHPMailer Command Injection Vulnerability
before 5.2.18
Which Phpmailer vulnerabilities are being exploited?
1 flaw is on the government list of vulnerabilities known to be exploited. These are the ones criminals are using now, so they go first, whatever their severity score says.
- 9.8PHPMailer Command Injection Vulnerability
PHPMailer contains a command injection vulnerability because it fails to sanitize user-supplied input.
Which Phpmailer flaws are most likely to be used?
Ranked by the latest exploit-likelihood forecast: the chance each flaw is used in an attack in the next 30 days. A high severity score on its own doesn't tell you that. Flaws shared by many other makers' products are left out.
- >99%
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...
- 98%CVE-2016-10045Critical
The isMail transport in PHPMailer before 5.2.20 might allow remote attackers to pass extra parameters to the mail command and consequently execute arbitrary code by leveraging improper interaction between the...
- 3.8%CVE-2020-13625High
PHPMailer before 6.1.6 contains an output escaping bug when the name of a file attachment contains a double quote character.
- 3.1%CVE-2020-36326Critical
PHPMailer 6.1.8 through 6.4.0 allows object injection through Phar Deserialization via addAttachment with a UNC pathname.
- 2.8%CVE-2021-34551High
PHPMailer before 6.5.0 on Windows allows remote code execution if lang_path is untrusted data and has a UNC pathname.
- 2.4%CVE-2017-11503Medium
PHPMailer 5.2.23 has XSS in the "From Email Address" and "To Email Address" fields of code_generator.php.
- 2.3%CVE-2021-3603High
PHPMailer 6.4.1 and earlier contain a vulnerability that can result in untrusted code being called (if such code is injected into the host project's scope by other means).
- 2.2%CVE-2018-19296High
PHPMailer before 5.2.27 and 6.x before 6.0.6 is vulnerable to an object injection attack.
- 2.1%CVE-2017-5223Medium
An issue was discovered in PHPMailer before 5.2.22.
- 2.0%CVE-2015-8476Medium
Multiple CRLF injection vulnerabilities in PHPMailer before 5.2.14 allow attackers to inject arbitrary SMTP commands via CRLF sequences in an (1) email address to the validateAddress function in class.phpmailer.php...
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1 flaw being exploited affects software Acme tracks
PHPMailer contains a command injection vulnerability because it fails to sanitize user-supplied input. Specifically, this issue affects the 'mail()' function of 'class.phpmailer.php' script. An attacker can exploit this issue to execute arbitrary code within the context of the application. Failed exploit attempts will result in a denial-of-service condition.
- Matched to
- Phpmailer on Acme's software list
- What to do
- Patch first, then check for signs of use
Sent to the alert recipients Acme chose. Also in the app and to Acme's webhook.
We track 10 published vulnerabilities listed under the name Phpmailer, across 51 versions. The most recent Phpmailer flaw added to the known-exploited list is CVE-2016-10033, on 7 July 2025.
1 is on the list of flaws known to be exploited. The most recently added is CVE-2016-10033.
Each flaw names its own versions, usually as ranges. The newest, CVE-2016-10033, affects before 5.2.18. The versions for every exploited flaw are listed on this page.
Create a Precursor Intelligence account and track Phpmailer. We match it against every published flaw, give each one a risk score from 0 to 100 and keep watching, so you hear about new ones as soon as we know, by email, in the app or by webhook.