Vulnerability in Phpmailer
CVE-2021-3603
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). If the $patternselect parameter to validateAddress() is set to 'php' (the default, defined by PHPMailer::$validator), and the global namespace contains a function called php, it will be called in preference to the built-in validator of the same name. Mitigated in PHPMailer 6.5.0 by denying the use of simple strings as validator function names.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 8.1 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.023 (82.3th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 82nd percentile — 82.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.023 · newest: 0.023 · change: 0.000
Affected products
- Phpmailer — versions unspecified
- Phpmailer Project
- Fedoraproject Fedora — versions 33, 34
Weakness classification (CWE)
Public proof-of-concept exploits
References
- www.huntr.dev/bounties/1-PHPMailer/PHPMailer/ (Product)
- github.com/PHPMailer/PHPMailer/commit/45f3c18dc6a2de1cb1bf49b9b249a9ee36a5f7f3 (Patch, Third Party Advisory)
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/… (vendor-advisory)
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/… (vendor-advisory)
Frequently asked questions
- What is CVE-2021-3603?
- CVE-2021-3603 is a high-severity vulnerability in Phpmailer, classified under Inclusion of Functionality from Untrusted Control Sphere. CVSS score: 8.1/10. Published 2021-06-17.
- How severe is CVE-2021-3603?
- High severity. CVSS v3 base score is 8.1 out of 10.
- Is CVE-2021-3603 known to be exploited?
- 3 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.