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.

The remote Ubuntu 16.04 ESM / 18.04 ESM / 20.04 ESM / 22.04 ESM host has a package installed that is affected by multiple vulnerabilities as referenced in the USN-5956-1 advisory.

    Dawid Golunski discovered that PHPMailer was not properly escaping user input data used as arguments to     functions executed by the system shell. An attacker could possibly use this issue to execute arbitrary     code. This issue only affected Ubuntu 16.04 ESM. (CVE-2016-10033, CVE-2016-10045)

    It was discovered that PHPMailer was not properly escaping characters in certain fields of the     code_generator.php example code. An attacker could possibly use this issue to conduct cross-site scripting     (XSS) attacks. This issue was only fixed in Ubuntu 16.04 ESM and Ubuntu 18.04 ESM. (CVE-2017-11503)

    Yongxiang Li discovered that PHPMailer was not properly converting relative paths provided as user input     when adding attachments to messages, which could lead to relative image URLs being treated as absolute     local file paths and added as attachments. An attacker could possibly use this issue to access     unauthorized resources and expose sensitive information. This issue only affected Ubuntu 16.04 ESM.
    (CVE-2017-5223)

    Sehun Oh discovered that PHPMailer was not properly processing untrusted non-local file attachments, which     could lead to an object injection. An attacker could possibly use this issue to execute arbitrary code.
    This issue only affected Ubuntu 16.04 ESM. (CVE-2018-19296)

    Elar Lang discovered that PHPMailer was not properly escaping file attachment names, which could lead to a     misinterpretation of file types by entities processing the message. An attacker could possibly use this     issue to bypass attachment filters. This issue was only fixed in Ubuntu 16.04 ESM and Ubuntu 20.04 ESM.
    (CVE-2020-13625)

    It was discovered that PHPMailer was not properly handling callables in its validateAddress function,     which could result in untrusted code being called should the global namespace contain a function called     'php'. An attacker could possibly use this issue to execute arbitrary code. This issue was only fixed in     Ubuntu 20.04 ESM and Ubuntu 22.04 ESM. (CVE-2021-3603)

Tenable has extracted the preceding description block directly from the Ubuntu security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

It was discovered that there was a local file disclosure vulnerability in libphp-phpmailer, a email transfer class for PHP, where insufficient parsing of HTML messages could potentially be used by attacker to read a local file.

For Debian 7 'Wheezy', this issue has been fixed in libphp-phpmailer version 5.1-1.3+deb7u1.

We recommend that you upgrade your libphp-phpmailer packages.

NOTE: Tenable Network Security has extracted the preceding description block directly from the DLA security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.

**Version 5.2.22** (January 5th 2017)

  - **SECURITY** Fix     [CVE-2017-5223](https://web.nvd.nist.gov/view/vuln/detai     l?vulnId=CVE-2017-5223), local file disclosure     vulnerability if content passed to `msgHTML()` is     sourced from unfiltered user input. Reported by     Yongxiang Li of Asiasecurity. The fix for this means     that calls to `msgHTML()` without a `$basedir` will not     import images with relative URLs, and relative URLs     containing `..` will be ignored.

  - Add simple contact form example

  - Emoji in test content

----

**Version 5.2.21** (December 28th 2016)

  - Fix missed number update in version file - no functional     changes

----

**Version 5.2.20** (December 28th 2016)

  - **SECURITY** Critical security update for CVE-2016-10045     please update now! Thanks to [Dawid     Golunski](https://legalhackers.com) and Paul Buonopane     (Zenexer).

----

** Version 5.2.19** (December 26th 2016)

  - Minor cleanup

** Version 5.2.18** (December 24th 2016)

  - **SECURITY** Critical security update for CVE-2016-10033     please update now! Thanks to [Dawid     Golunski](https://legalhackers.com).

  - Add ability to extract the SMTP transaction ID from some     common SMTP success messages

  - Minor documentation tweaks

** Version 5.2.17** (December 9th 2016)

  - This is officially the last feature release of 5.2.
    Security fixes only from now on; use PHPMailer 6.0!

  - Allow DKIM private key to be provided as a string

  - Provide mechanism to allow overriding of boundary and     message ID creation

  - Improve Brazilian Portuguese, Spanish, Swedish,     Romanian, and German translations

  - PHP 7.1 support for Travis-CI

  - Fix some language codes

  - Add security notices

  - Improve DKIM compatibility in older PHP versions

  - Improve trapping and capture of SMTP connection errors

  - Improve passthrough of error levels for debug output

  - PHPDoc cleanup

Note that Tenable Network Security has extracted the preceding description block directly from the Fedora update system website.
Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.

SecurityFocus reports :

PHPMailer is prone to an local information-disclosure vulnerability.
Attackers can exploit this issue to obtain sensitive information that may aid in launching further attacks.

ID	Name	Product	Family	Severity
172589	Ubuntu 16.04 ESM / 18.04 ESM / 20.04 ESM / 22.04 ESM : PHPMailer vulnerabilities (USN-5956-1)	Nessus	Ubuntu Local Security Checks	critical
97029	Debian DLA-817-1 : libphp-phpmailer security update	Nessus	Debian Local Security Checks	medium
96574	Fedora 24 : php-PHPMailer (2017-c3dc97e1e1)	Nessus	Fedora Local Security Checks	critical
96471	FreeBSD : phpmailer -- Remote Code Execution (7ae0be99-d8bb-11e6-9b7f-d43d7e971a1b)	Nessus	FreeBSD Local Security Checks	medium

Detections

Analytics

CVE-2017-5223

medium

Tenable Plugins

critical

medium

critical

medium