CVE-2021-25641

published 2021-06-01

CVE-2021-25641: Each Apache Dubbo server will set a serialization id to tell the clients which serialization protocol it is working on. But for Dubbo versions before 2.7.8 or…

Priority P2 71 critical 9.8 CVSS 3.1

AV N AC L PR N UI N S U C H I H A H

Each Apache Dubbo server will set a serialization id to tell the clients which serialization protocol it is working on. But for Dubbo versions before 2.7.8 or 2.6.9, an attacker can choose which serialization id the Provider will use by tampering with the byte preamble flags, aka, not following the server's instruction. This means that if a weak deserializer such as the Kryo and FST are somehow in code scope (e.g. if Kryo is somehow a part of a dependency), a remote unauthenticated attacker can tell the Provider to use the weak deserializer, and then proceed to exploit it.

Affected

4 ranges

Vendor	Product	Version range	Fixed in
apache	dubbo	>= 2.5.0 < 2.6.9	2.6.9
apache	dubbo	>= 2.7.0 < 2.7.8	2.7.8
apache_software_foundation	apache_dubbo	>= Apache Dubbo 2.6.x < 2.6.9	2.6.9
apache_software_foundation	apache_dubbo	>= Apache Dubbo 2.7.x < 2.7.8	2.7.8

CVSS provenance

nvd v3.1 9.8 CRITICAL CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

nvd v2.0 7.5 HIGH AV:N/AC:L/Au:N/C:P/I:P/A:P

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CWE-502