This High severity Insecure Deserialization vulnerability was introduced in versions 2.0.1, 3.2.2, 6.3.0, 7.0.0, and 7.1.0 of Crowd Data Center and Server.

This Insecure Deserialization vulnerability, with a CVSS Score of 7.5 and a CVSS Vector of CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N allows an unauthenticated attacker to access local and remote content which has no impact to confidentiality, high impact to integrity, no impact to availability, and requires no user interaction.

Atlassian recommends that Crowd Data Center and Server customers upgrade to latest version, if you are unable to do so, upgrade your instance to one of the specified supported fixed versions:

• Crowd Data Center and Server 7.1: Upgrade to a release greater than or equal to 7.1.2

See the release notes (https://confluence.atlassian.com/crowd/crowd-release-notes-199094.html). You can download the latest version of Crowd Data Center and Server from the download center (https://www.atlassian.com/software/crowd/download-archive).

The National Vulnerability Database provides the following description for this vulnerability: ctorName in index.js in kind-of v6.0.2 allows external user input to overwrite certain internal attributes via a conflicting name, as demonstrated by 'constructor': {'name':'Symbol'}. Hence, a crafted payload can overwrite this builtin attribute to manipulate the type detection result.