CVE-2021-29485
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.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (1.99%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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 3.1
- 8.8 HIGHCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 1.99% probability · 79th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-502
- Affected
- ratpack project/ratpack
- Source
- security-advisories@github.com
References
- https://github.com/ratpack/ratpack/security/advisories/GHSA-hc33-32vw-rpp9Third Party Advisory
- https://mvnrepository.com/artifact/io.ratpack/ratpack-coreRelease Notes, Third Party Advisory
- https://github.com/ratpack/ratpack/security/advisories/GHSA-hc33-32vw-rpp9Third Party Advisory
- https://mvnrepository.com/artifact/io.ratpack/ratpack-coreRelease Notes, Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.