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Fencer Intel
critical 9.8

CVE-2021-30179 json

Apache Dubbo Pre-auth RCE via Java deserialization in the Generic filter

published 5y ago modified 4mo ago also GHSA-5mc7-m686-p6jg , EUVD-2022-1324

cvss
9.8
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
4.1%
EPSS 4.1% chance of exploitation in 30 days, percentile 90%
public exploits
0
none known

Summary

Apache Dubbo prior to 2.6.9 and 2.7.9 by default supports generic calls to arbitrary methods exposed by provider interfaces. These invocations are handled by the GenericFilter which will find the service and method specified in the first arguments of the invocation and use the Java Reflection API to make the final call. The signature for the $invoke or $invokeAsync methods is Ljava/lang/String;[Ljava/lang/String;[Ljava/lang/Object; where the first argument is the name of the method to invoke, the second one is an array with the parameter types for the method being invoked and the third one is an array with the actual call arguments. In addition, the caller also needs to set an RPC attachment specifying that the call is a generic call and how to decode the arguments. The possible values are: - true - raw.return - nativejava - bean - protobuf-json An attacker can control this RPC attachment and set it to nativejava to force the java deserialization of the byte array located in the third argument.

Patch / fix

  • maven org.apache.dubbo:dubbo 2.7.10
  • maven com.alibaba:dubbo 2.6.9
  • Apache Software Foundation Apache Dubbo 2.6.9, 2.7.9

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Exploit prediction

4.08% chance of exploitation in the next 30 days, higher than 90% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by version score vector
NVD 3.1 9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
NVD 2.0 7.5 AV:N/AC:L/Au:N/C:P/I:P/A:P
GitHub 3.1 9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected packages

ecosystem package affected fixed in
maven org.apache.dubbo:dubbo
>=2.5.0, <2.7.10
2.7.10
maven com.alibaba:dubbo
>=2.5.0, <2.6.9
2.6.9

Affected products

  • Apache Software Foundation Apache Dubbo

Classification

Weakness
  • CWE-502 Deserialization of Untrusted Data

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.