CVE-2016-10033PHPMailer Command Injection Vulnerability

BOD 26-04 remediation window

With CISA's SSVC answers for this CVE (automatable: yes, technical impact: total), BOD 26-04 Table 1 gives 3 days and forensic triage on a publicly exposed asset (row 1) and 3 days and forensic triage on an asset that is not publicly exposed (row 9) ^S06. The catalogue due date, 21 days after the date added, was set before BOD 26-04 took effect on 10 June 2026 ^S06. The directive binds US federal civilian executive branch agencies only.

What CISA says

Short description

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.

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.

Notes

This vulnerability could affect an open-source component, third-party library, protocol, or proprietary implementation that could be used by different products. For more information, please see: https://github.com/PHPMailer/PHPMailer/releases/tag/v5.2.18 ; https://github.com/advisories/GHSA-5f37-gxvh-23v6 ; https://nvd.nist.gov/vuln/detail/CVE-2016-10033

CWE in the catalogue

CWE-77, CWE-88

Official links

• CISA KEV catalogue entry cisa.gov
• NVD record nvd.nist.gov

Vendor advisory and patch links

References NVD tags Vendor Advisory or Patch, exactly as NVD lists them.

• http://seclists.org/fulldisclosure/2016/Dec/78 Mailing List, Patch, Third Party Advisory
• https://github.com/PHPMailer/PHPMailer/releases/tag/v5.2.18 Patch, Vendor Advisory
• https://github.com/PHPMailer/PHPMailer/wiki/About-the-CVE-2016-10033-and-CVE-2016-10045-vulnerabilities Patch, Vendor Advisory
• https://legalhackers.com/advisories/PHPMailer-Exploit-Remote-Code-Exec-CVE-2016-10033-Vuln.html Exploit, Patch, Third Party Advisory
• https://www.exploit-db.com/exploits/40968/ Exploit, Patch, Third Party Advisory, VDB Entry
• https://www.exploit-db.com/exploits/40970/ Exploit, Patch, Third Party Advisory, VDB Entry

Links in CISA's notes

• https://github.com/PHPMailer/PHPMailer/releases/tag/v5.2.18
• https://github.com/advisories/GHSA-5f37-gxvh-23v6
• https://nvd.nist.gov/vuln/detail/CVE-2016-10033

NVD details

CWE (NVD)

CWE-88 by nvd@nist.gov

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CVSS versions in NVD

V2, V31

Last modified in NVD

2026-06-17T00:38:55.477

Where each value comes from

This product uses data from the NVD API but is not endorsed or certified by the NVD. CISA does not endorse Sysprobs. Methodology.