Vulnerabilities
Misconfiguration
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CVE Vulnerabilities

CVE-2018-20148

Deserialization of Untrusted Data

Published: Dec 14, 2018 | Modified: Nov 21, 2024
CVSS 3.x
9.8
CRITICAL
Source:
NVD
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS 2.x
7.5 HIGH
AV:N/AC:L/Au:N/C:P/I:P/A:P
RedHat/V2
RedHat/V3
Ubuntu
MEDIUM
Vulnerability-free packages from our partners
Additional information
NVDhttps://nvd.nist.gov/vuln/detail/CVE-2018-20148
CWEhttps://cwe.mitre.org/data/definitions/502.html

In WordPress before 4.9.9 and 5.x before 5.0.1, contributors could conduct PHP object injection attacks via crafted metadata in a wp.getMediaItem XMLRPC call. This is caused by mishandling of serialized data at phar:// URLs in the wp_get_attachment_thumb_file function in wp-includes/post.php.

Weakness

The product deserializes untrusted data without sufficiently ensuring that the resulting data will be valid.

Affected Software

Name Vendor Start Version End Version
Wordpress Wordpress * 4.9.9 (excluding)
Wordpress Wordpress 5.0 (including) 5.0.1 (excluding)
Wordpress Ubuntu bionic *
Wordpress Ubuntu cosmic *
Wordpress Ubuntu esm-apps/bionic *
Wordpress Ubuntu esm-apps/xenial *
Wordpress Ubuntu trusty *
Wordpress Ubuntu upstream *
Wordpress Ubuntu xenial *

Potential Mitigations

  • Make fields transient to protect them from deserialization.
  • An attempt to serialize and then deserialize a class containing transient fields will result in NULLs where the transient data should be. This is an excellent way to prevent time, environment-based, or sensitive variables from being carried over and used improperly.

References

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