GHSA-f7hx-fqxw-rvvj

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Source
https://github.com/advisories/GHSA-f7hx-fqxw-rvvj
Import Source
https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2020/05/GHSA-f7hx-fqxw-rvvj/GHSA-f7hx-fqxw-rvvj.json
JSON Data
https://api.osv.dev/v1/vulns/GHSA-f7hx-fqxw-rvvj
Aliases
Published
2020-05-27T16:37:02Z
Modified
2024-02-21T05:26:07.434661Z
Severity
  • 7.5 (High) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N CVSS Calculator
Summary
Insufficient output escaping of attachment names in PHPMailer
Details

Impact

CWE-116: Incorrect output escaping.

An attachment added like this (note the double quote within the attachment name, which is entirely valid):

$mail->addAttachment('/tmp/attachment.tmp', 'filename.html";.jpg');

Will result in a message containing these headers:

Content-Type: application/octet-stream; name="filename.html";.jpg"
Content-Disposition: attachment; filename="filename.html";.jpg"

The attachment will be named filename.html, and the trailing ";.jpg" will be ignored. Mail filters that reject .html attachments but permit .jpg attachments may be fooled by this.

Note that the MIME type itself is obtained automatically from the source filename (in this case attachment.tmp, which maps to a generic application/octet-stream type), and not the name given to the attachment (though these are the same if a separate name is not provided), though it can be set explicitly in other parameters to attachment methods.

Patches

Patched in PHPMailer 6.1.6 by escaping double quotes within the name using a backslash, as per RFC822 section 3.4.1, resulting in correctly escaped headers like this:

Content-Type: application/octet-stream; name="filename.html\";.jpg"
Content-Disposition: attachment; filename="filename.html\";.jpg"

Workarounds

Reject or filter names and filenames containing double quote (") characters before passing them to attachment functions such as addAttachment().

References

CVE-2020-13625. PHPMailer 6.1.6 release

For more information

If you have any questions or comments about this advisory: * Open an issue in the PHPMailer repo

References

Affected packages

Packagist / phpmailer/phpmailer

Package

Name
phpmailer/phpmailer
Purl
pkg:composer/phpmailer/phpmailer

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
6.1.6

Affected versions

v5.*

v5.2.2
v5.2.4
v5.2.5
v5.2.6
v5.2.7
v5.2.8
v5.2.9
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
v5.2.20
v5.2.21
v5.2.22
v5.2.23
v5.2.24
v5.2.25
v5.2.26
v5.2.27
v5.2.28

v6.*

v6.0.0rc1
v6.0.0rc2
v6.0.0rc3
v6.0.0rc4
v6.0.0rc5
v6.0.0
v6.0.1
v6.0.2
v6.0.3
v6.0.4
v6.0.5
v6.0.6
v6.0.7
v6.1.0
v6.1.1
v6.1.2
v6.1.3
v6.1.4
v6.1.5