CVE-2022-21653: Hash collision in typelevel jawn
Summary
CVE-2022-21653: Hash collision in typelevel jawn. Affects org.typelevel:jawn-parser versions < 1.3.2. Fixed in 1.3.2. How to fix ↓
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Background
The package under scrutiny is org.typelevel:jawn-parser, which is a JSON parser for Scala. It provides a set of traits, including org.typelevel.jawn.SimpleFacade and org.typelevel.jawn.MutableFacade, which can be extended to customize JSON parsing behavior. However, extenders who don't override objectContext() are vulnerable to a hash collision attack. This vulnerability affects various implementations inherited from the library, such as org.http4s::http4s-play-json, org.typelevel::jawn-ast (< 0.8.0), org.typelevel::jawn-play, org.typelevel::jawn-rojoma, and org.typelevel::jawn-spray. Unaffected implementations include io.argonaut::argonaut-jawn, io.circe::circe-parser, org.typelevel::jawn-ast (>= 0.8.0), org.typelevel::jawn-json4s, and org.typelevel::jawn-argonaut.
Vulnerability Detail
The vulnerability arises from a hash collision attack on the objectContext() method in the affected implementations. Extenders who don't override this method are susceptible to the attack. The impact of this vulnerability is moderate, as it allows an attacker to exploit hash collisions to cause denial of service (DoS) by consuming excessive CPU resources. The vulnerability has been assigned a CVSS score of 5.9.
How To Fix
Minimum fixed version
1.3.2
This is the first release that contains the fix.
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Workaround
If updating the library is not immediately feasible, a workaround is to override the objectContext() method in the affected implementations to use a collision-safe collection. The patch provided in the GitHub pull request (https://github.com/typelevel/jawn/pull/390/files) offers an example of how to implement this workaround in both SimpleFacade and MutableFacade.
Conclusion
In conclusion, the org.typelevel:jawn-parser package is vulnerable to a hash collision attack in certain implementations. It is crucial to update the library to version 1.3.2 or apply the provided workaround to mitigate the risk of denial of service attacks. For further support on vulnerability remediation, please contact DevNack.com.
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FAQ
The vulnerability affects implementations inherited from the jawn-parser library, including org.http4s::http4s-play-json, org.typelevel::jawn-ast (< 0.8.0), org.typelevel::jawn-play, org.typelevel::jawn-rojoma, and org.typelevel::jawn-spray.
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The vulnerability allows an attacker to exploit hash collisions to cause denial of service (DoS) by consuming excessive CPU resources. However, it does not enable remote code execution or unauthorized access to sensitive information.
Yes, a workaround is to override the objectContext() method in the affected implementations to use a collision-safe collection. The provided patch in the GitHub pull request (https://github.com/typelevel/jawn/pull/390/files) demonstrates how to implement this workaround.
Yes, the vulnerability can be fixed by updating the jawn-parser library to version 1.3.2, which includes the necessary patches to address the issue.
