CVE-2021-29480

Description

### Impact The client side session module uses the application startup time as the signing key by default. This means that if an attacker can determine this time, and if encryption is not also used (which is recommended, but is not on by default), the session data could be tampered with by someone with the ability to write cookies. The default configuration is unsuitable for production use as an application restart renders all sessions invalid and is not multi-host compatible, but its use is not actively prevented. ### Vulnerability Location https://github.com/ratpack/ratpack/blob/29434f7ac6fd4b36a4495429b70f4c8163100332/ratpack-session/src/main/java/ratpack/session/clientside/ClientSideSessionConfig.java#L29 ### Patches As of Ratpack 1.9.0 the default value is a securely randomly generated value, generated at application startup time. ### Workarounds Supply an alternative signing key, as per the documentation's recommendation.

How to fix CVE-2021-29480

To remediate CVE-2021-29480, upgrade the affected package to a fixed version below.

• —upgrade to 1.9.0 or later

Is CVE-2021-29480 being exploited?

Low — EPSS is 0.1%, meaning exploitation activity has not been observed at scale.

Affected packages (1)

• from 0, < 1.9.0

CVSS scores

References (4)

• ADVISORYnvd.nist.gov/vuln/detail/CVE-2021-29480
• PATCHgithub.com/ratpack/ratpack
• WEBgithub.com/ratpack/ratpack/blob/29434f7ac6fd4b36a4495429b70f4c8163100332/ratpack-session/src/main/java/ratpack/session/clientside/ClientSideSessionConfig.java#L29
• WEBgithub.com/ratpack/ratpack/security/advisories/GHSA-2cc5-23r7-vc4v