CVE-2023-42809

Public Exploit
Redisson unsafe deserialization vulnerability

Description

Redisson is a Java Redis client that uses the Netty framework. Prior to version 3.22.0, some of the messages received from the Redis server contain Java objects that the client deserializes without further validation. Attackers that manage to trick clients into communicating with a malicious server can include especially crafted objects in its responses that, once deserialized by the client, force it to execute arbitrary code. This can be abused to take control of the machine the client is running in. Version 3.22.0 contains a patch for this issue. Some post-fix advice is available. Do NOT use `Kryo5Codec` as deserialization codec, as it is still vulnerable to arbitrary object deserialization due to the `setRegistrationRequired(false)` call. On the contrary, `KryoCodec` is safe to use. The fix applied to `SerializationCodec` only consists of adding an optional allowlist of class names, even though making this behavior the default is recommended. When instantiating `SerializationCodec` please use the `SerializationCodec(ClassLoader classLoader, Set<String> allowedClasses)` constructor to restrict the allowed classes for deserialization.

Category

9.6
CVSS
Severity: Critical
CVSS 3.1 •
EPSS 0.70% Top 30%
Third-Party Advisory github.com
Affected: redisson redisson
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2023-42809?
CVE-2023-42809 has been scored as a critical severity vulnerability.
How to fix CVE-2023-42809?
To fix CVE-2023-42809, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2023-42809 being actively exploited in the wild?
It is possible that CVE-2023-42809 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2023-42809?
CVE-2023-42809 affects redisson redisson.
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