XWiki Platform Web Templates are templates for XWiki Platform, a generic wiki platform. Through the suggestion feature, string and list properties of objects the user shouldn't have access to can be accessed in versions prior to 13.10.4 and 14.2. This includes private personal information like email addresses and salted password hashes of registered users but also other information stored in properties of objects. Sensitive configuration fields like passwords for LDAP or SMTP servers could be accessed. By exploiting an additional vulnerability, this issue can even be exploited on private wikis at least for string properties. The issue is patched in version 13.10.4 and 14.2. Password properties are no longer displayed and rights are checked for other properties. A workaround is available. The template file `suggest.vm` can be replaced by a patched version without upgrading or restarting XWiki unless it has been overridden, in which case the overridden template should be patched, too. This might need adjustments for older versions, though.
XWiki Platform Old Core is a core package for XWiki Platform, a generic wiki platform. Prior to versions 13.1.0.5 and 14.3-rc-1, some resources are missing a check for inactive (not yet activated or disabled) users in XWiki, including the REST service. This means a disabled user can enable themselves using a REST call. On the same way some resources handler created by extensions are not protected by default, so an inactive user could perform actions for such extensions. This issue has existed since at least version 1.1 of XWiki for instance configured with the email activation required for new users. Now it's more critical for versions 11.3-rc-1 and later since the maintainers provided the capability to disable user without deleting them and encouraged using that feature. XWiki 14.3-rc-1 and XWiki 13.10.5 contain a patch. There is no workaround for this other than upgrading XWiki.
XWiki Platform Old Core is a core package for XWiki Platform, a generic wiki platform. Starting in versions 11.3.7, 11.0.3, and 12.0RC1, it is possible to exploit a bug in XWikiRights resolution of groups to obtain privilege escalation. More specifically, editing a right with the object editor leads to adding a supplementary empty value to groups which is then resolved as a reference to XWiki.WebHome page. Adding an XWikiGroup xobject to that page then transforms it to a group, any user put in that group would then obtain the privileges related to the edited right. Note that this security issue is normally mitigated by the fact that XWiki.WebHome (and XWiki space in general) should be protected by default for edit rights. The problem has been patched in XWiki 13.10.4 and 14.2RC1 to not consider anymore empty values in XWikiRights. It's possible to work around the problem by setting appropriate rights on XWiki.WebHome page to prevent users to edit it.
XWiki Platform is a generic wiki platform offering runtime services for applications built on top of it. The XWiki Crypto API will generate X509 certificates signed by default using SHA1 with RSA, which is not considered safe anymore for use in certificate signatures, due to the risk of collisions with SHA1. The problem has been patched in XWiki version 13.10.6, 14.3.1 and 14.4-rc-1. Since then, the Crypto API will generate X509 certificates signed by default using SHA256 with RSA. Administrators are advised to upgrade their XWiki installation to one of the patched versions. If the upgrade is not possible, it is possible to patch the module xwiki-platform-crypto in a local installation by applying the change exposed in 26728f3 and re-compiling the module.