CVE-2023-48240
Vulnérabilité critique dans xwiki-platform (xwiki)
Description
XWiki Platform is a generic wiki platform. The rendered diff in XWiki embeds images to be able to compare the contents and not display a difference for an actually unchanged image. For this, XWiki requests all embedded images on the server side. These requests are also sent for images from other domains and include all cookies that were sent in the original request to ensure that images with restricted view right can be compared. Starting in version 11.10.1 and prior to versions 14.10.15, 15.5.1, and 15.6, this allows an attacker to steal login and session cookies that allow impersonating the current user who views the diff. The attack can be triggered with an image that references the rendered diff, thus making it easy to trigger. Apart from stealing login cookies, this also allows server-side request forgery (the result of any successful request is returned in the image's source) and viewing protected content as once a resource is cached, it is returned for all users. As only successful requests are cached, the cache will be filled by the first user who is allowed to access the resource. This has been patched in XWiki 14.10.15, 15.5.1 and 15.6. The rendered diff now only downloads images from trusted domains. Further, cookies are only sent when the image's domain is the same the requested domain. The cache has been changed to be specific for each user. As a workaround, the image embedding feature can be disabled by deleting `xwiki-platform-diff-xml-<version>.jar` in `WEB-INF/lib/`.
Gravité et risque d'exploitation
CVE-2023-48240 obtient un score CVSS de 9.1/10, soit une gravité critique. Selon le modèle EPSS, la probabilité qu'elle soit exploitée dans les 30 prochains jours est de 0.71 %, ce qui la place devant 52.7 % des CVE référencées.
Que faire ?
- Vérifiez si xwiki-platform (versions >= 15.6-rc-1, < 15.6, >= 15.0-rc-1, < 15.5.1, >= 11.10.1, < 14.10.15) est présent sur votre parc.
- Appliquez le correctif ou la version corrigée indiqués dans les références de l'éditeur.
- À défaut de correctif, limitez l'exposition (filtrage réseau, désactivation du composant).
- Automatisez la détection : les agents CVE Heimdall (gratuits, open source) corrèlent l'inventaire de vos serveurs avec la base CVE.