Local file disclosure in PHPMailer
The advisory, in context
An issue was discovered in PHPMailer before 5.2.22. PHPMailer's msgHTML method applies transformations to an HTML document to make it usable as an email message body. One of the transformations is to convert relative image URLs into attachments using a script-provided base directory. If no base directory is provided, it resolves to /, meaning that relative image URLs get treated as absolute local file paths and added as attachments. To form a remote vulnerability, the msgHTML method must be called, passed an unfiltered, user-supplied HTML document, and must not set a base directory.
Impact
Arbitrary local files can be attached to email messages.
Patches
Fixed in 5.2.22
Workarounds
Validate input before using user-supplied file paths.
References
https://nvd.nist.gov/vuln/detail/CVE-2017-5223
For more information
If you have any questions or comments about this advisory:
- Open a private issue in the PHPMailer project
Affected packages
Start with the recorded fix for your release branch. Check your installed version and test compatibility before upgrading. Fixing this advisory does not rule out other vulnerabilities in the release.
From 5.0.0 before 5.2.22
Fixed in 5.2.22
19 explicitly affected versions
v5.2.10, v5.2.11, v5.2.12, v5.2.13, v5.2.14, v5.2.15, v5.2.16, v5.2.17, v5.2.18, v5.2.19, v5.2.2, v5.2.20, v5.2.21, v5.2.4, v5.2.5, v5.2.6, v5.2.7, v5.2.8, v5.2.9
View affected-version evidence
{
"ranges": [
{
"events": [
{
"introduced": "5.0.0"
},
{
"fixed": "5.2.22"
}
],
"type": "ECOSYSTEM"
}
],
"versions": [
"v5.2.10",
"v5.2.11",
"v5.2.12",
"v5.2.13",
"v5.2.14",
"v5.2.15",
"v5.2.16",
"v5.2.17",
"v5.2.18",
"v5.2.19",
"v5.2.2",
"v5.2.20",
"v5.2.21",
"v5.2.4",
"v5.2.5",
"v5.2.6",
"v5.2.7",
"v5.2.8",
"v5.2.9"
]
}References
- https://github.com/PHPMailer/PHPMailer/security/advisories/GHSA-4x5h-cr29-fhp6
- https://nvd.nist.gov/vuln/detail/CVE-2017-5223
- https://github.com/FriendsOfPHP/security-advisories/blob/master/phpmailer/phpmailer/CVE-2017-5223.yaml
- https://github.com/PHPMailer/PHPMailer/blob/master/SECURITY.md
- https://github.com/PHPMailer/PHPMailer/releases/tag/v5.2.22
- https://www.exploit-db.com/exploits/43056
- http://kalilinux.co/2017/01/12/phpmailer-cve-2017-5223-local-information-disclosure-vulnerability-analysis
- http://www.securityfocus.com/bid/95328