CVE-2025-27821: HDFS native client: Out of bounds write in URI parser of native HDFS client

Published Jan 23, 2026
·
Updated

Out-of-bounds Write vulnerability in Apache Hadoop HDFS native client.

This issue affects Apache Hadoop: from 3.2.0 before 3.4.2.

Users are recommended to upgrade to version 3.4.2, which fixes the issue.

Affected Software

3 affected componentsFixes available
Apache Hadoop>=3.2.0<3.4.2
maven/org.apache.hadoop:hadoop-hdfs-native-client>=3.2.0<3.4.2
3.4.2
Apache Hadoop>=3.2.0<3.4.2

Event History

Jan 26, 2026
CVE Published
via MITRE·09:44 AM
Data Sourced
via MITRE·09:44 AM
DescriptionWeakness
Data Sourced
via NVD·10:16 AM
DescriptionSeverityWeaknessAffected Software
Advisory Published
via GitHub·12:30 PM
Data Sourced
via GitHub·12:30 PM
DescriptionSeverityWeaknessAffected Software
Free Weekly Intel

Don't miss critical vulnerabilities

Join thousands of security professionals who receive our weekly digest of trending CVEs, zero-days, and exploited vulnerabilities.

No spam. Unsubscribe anytime.

Frequently Asked Questions

1

What is the severity of CVE-2025-27821?

CVE-2025-27821 is classified as a high severity out-of-bounds write vulnerability in the Apache Hadoop HDFS native client.

2

How do I fix CVE-2025-27821?

To fix CVE-2025-27821, upgrade Apache Hadoop from any version between 3.2.0 and before 3.4.2 to version 3.4.2 or later.

3

Which versions of Apache Hadoop are affected by CVE-2025-27821?

CVE-2025-27821 affects Apache Hadoop versions from 3.2.0 up to and including versions before 3.4.2.

4

What components does CVE-2025-27821 impact?

CVE-2025-27821 impacts the native HDFS client of Apache Hadoop.

5

Is there a workaround for CVE-2025-27821?

There are no official workarounds for CVE-2025-27821; the recommended action is an upgrade to the patched version.

Contact

SecAlerts Pty Ltd.
132 Wickham Terrace
Fortitude Valley,
QLD 4006, Australia
info@secalerts.co
By using SecAlerts services, you agree to our services end-user license agreement. This website is safeguarded by reCAPTCHA and governed by the Google Privacy Policy and Terms of Service. All names, logos, and brands of products are owned by their respective owners, and any usage of these names, logos, and brands for identification purposes only does not imply endorsement. If you possess any content that requires removal, please get in touch with us.
© 2026 SecAlerts Pty Ltd.
ABN: 70 645 966 203, ACN: 645 966 203