CVE-2021-29485 Information

Description

Ratpack is a toolkit for creating web applications. In versions prior to 1.9.0 a malicious attacker can achieve Remote Code Execution (RCE) via a maliciously crafted Java deserialization gadget chain leveraged against the Ratpack session store. If one’s application does not use Ratpack’s session mechanism it is not vulnerable. Ratpack 1.9.0 introduces a strict allow-list mechanism that mitigates this vulnerability when used. Two possible workarounds exist. The simplest mitigation for users of earlier versions is to reduce the likelihood of attackers being able to write to the session data store. Alternatively or additionally the allow-list mechanism could be manually back ported by providing an alternative implementation of SessionSerializer that uses an allow-list.

CVSS Vector

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Reference

https://mvnrepository.com/artifact/io.ratpack/ratpack-core https://github.com/ratpack/ratpack/security/advisories/GHSA-hc33-32vw-rpp9

Attack Complexity

LOW

Privileges Required

LOW

User Interaction Required

LOW

Scope

NONE

Confidentiality Impact

UNCHANGED

Integrity Impact

HIGH

Availability Impact

HIGH

Base Score

HIGH

Base Severity

8.8