CVE-2021-39235: Access mode of block tokens are not enforced

Severity: medium (CVSS 6.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.6% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-11-19 · updated 2026-06-17
Weakness: CWE-732

Description

In Apache Ozone before 1.2.0, Ozone Datanode doesn't check the access mode parameter of the block token. Authenticated users with valid READ block token can do any write operation on the same block.

Affected products

Apache Software Foundation Apache Ozone: before 1.2.0 — fixed in 1.2.0

How to fix

Upgrade to a fixed version: Apache Software Foundation Apache Ozone 1.2.0. Check the vendor advisory for mitigations.

References

http://www.openwall.com/lists/oss-security/2021/11/19/6
https://mail-archives.apache.org/mod_mbox/ozone-dev/202111.mbox/%3C93f88246-4320-7423-0dac-ec7a07f47455%40apache.org%3E
http://www.openwall.com/lists/oss-security/2021/11/19/6
https://mail-archives.apache.org/mod_mbox/ozone-dev/202111.mbox/%3C93f88246-4320-7423-0dac-ec7a07f47455%40apache.org%3E

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