Is It On KEV?

PHP PHPMailer

YES - ON THE CISA KEV LIST
CVE-2016-10033

PHPMailer Command Injection Vulnerability

CISA catalog due date2025-07-28
overdue since 2025-07-28
EPSS exploit probability (next 30 days)99.7% · 100percentile
From CVE publication to KEV listing3111 days (2016-12-30 → 2025-07-07)
Remediation window (KEV listing to due date)21 days
Days on the KEV list492 days
Date added to KEV2025-07-07
Known ransomware campaign useUnknown
VendorPHP
ProductPHPMailer
Weaknesses (CWE)CWE-77, CWE-88

PHP: 3 entries (0.2% of all KEV entries are from this vendor); 0 added in 2026.

BOD 26-04 note: this is the date printed in the CISA catalog. A federal agency's actual deadline is set by its SSVC tier - Act (3 days), Attend (14 days), Track (60 days), or the next scheduled upgrade - counted from the KEV listing date or the date the vulnerability is identified in its environment, whichever comes first. Use the tier helper on each CVE page for your own window.

Your BOD 26-04 window (SSVC tier helper)

Your remediation window ends:

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 (CISA)

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

References

Other KEV entries for this vendor: PHP

PHP - Vendors with KEV entries

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