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GHSA-5f37-gxvh-23v6

CriticalCVSS 9.8 / 10
Published Mar 5, 2020·Last modified Oct 22, 2025
Affected Components(0)

No affected components available

Description

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:

Risk Scores
Base Score
9.8

The vulnerability can be exploited over the network without needing physical access. It is easy for an attacker to exploit this vulnerability. An attacker does not need any special privileges or access rights. No user interaction is needed for the attacker to exploit this vulnerability. The impact is confined to the system where the vulnerability exists. There is a high impact on the confidentiality of the information. There is a high impact on the integrity of the data. There is a high impact on the availability of the system.

Threat Intelligence
9.8

Active exploitation in the wild has been confirmed. Immediate patching or mitigation is required.

EPSS
99.71%

The exploit probability is critical. The vulnerability is very likely to be exploited in the next 30 days.

Exploit
Not available

We did not find any exploit available. Neither in GitHub repositories nor in the Exploit-Database.

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