CVE-2021-22160

Authentication with JWT allows use of “none”-algorithm

Description

If Apache Pulsar is configured to authenticate clients using tokens based on JSON Web Tokens (JWT), the signature of the token is not validated if the algorithm of the presented token is set to "none". This allows an attacker to connect to Pulsar instances as any user (incl. admins).

Category

9.8
CVSS
Severity: Critical
CVSS 3.1 •
CVSS 2.0 •
EPSS 7.83% Top 10%
Vendor Advisory apache.org Vendor Advisory apache.org
Affected: Apache Software Foundation Apache Pulsar
Published at:
Updated at:

References

Link Tags
https://lists.apache.org/thread.html/r347650d15a3e9c5f58b83e918b6ad6dedc2a63d3eb63da8e6a7be87e%40%3Cusers.pulsar.apache.org%3E mailing list vendor advisory
https://lists.apache.org/thread.html/rf2e90942996dceebac8296abf39257cfeb5ae918f82f7af3d37a48c5%40%3Cdev.pulsar.apache.org%3E mailing list
https://lists.apache.org/thread.html/ra49cb62105154e4795b259c79a6b27d63bfa2ab5787ff8529b089550%40%3Cdev.pulsar.apache.org%3E mailing list
https://lists.apache.org/thread.html/ra49cb62105154e4795b259c79a6b27d63bfa2ab5787ff8529b089550%40%3Cusers.pulsar.apache.org%3E mailing list
https://lists.apache.org/thread.html/r8e545559781231a83bf0644548c660255859e52feb86bbfcd42590da%40%3Cdev.pulsar.apache.org%3E mailing list
https://lists.apache.org/thread.html/r9a12b4da2f26ce9b8f7e7117a879efaa973dab7e54717bbc7923fab1%40%3Cdev.pulsar.apache.org%3E mailing list vendor advisory
https://lists.apache.org/thread.html/rbe845aa1573a61769b9c5916c62971f4b10de87c2ea5f38a97f0cf84%40%3Cdev.pulsar.apache.org%3E mailing list
https://lists.apache.org/thread.html/rca54f4b26ba5e6f2e39732b47ec51640e89f57e3b6a38ac3bab314df%40%3Cdev.pulsar.apache.org%3E mailing list

Frequently Asked Questions

What is the severity of CVE-2021-22160?
CVE-2021-22160 has been scored as a critical severity vulnerability.
How to fix CVE-2021-22160?
To fix CVE-2021-22160, 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-2021-22160 being actively exploited in the wild?
It is possible that CVE-2021-22160 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~8% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-22160?
CVE-2021-22160 affects Apache Software Foundation Apache Pulsar.
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