CVE-2021-25642Public exploitNetwork attack vector

Command execution via unrestricted ZooKeeper object deserialization

Published Aug 25, 2022 · Updated Aug 3, 2024

Unsafe deserialization in affected Apache Hadoop YARN releases allows remote authenticated users to execute commands as the YARN user. ZKConfigurationStore passes scheduler data read from ZooKeeper to ObjectInputStream without restricting deserialized classes, enabling gadget-chain execution. Exposure requires CapacityScheduler to use the optional ZooKeeper-backed configuration store and the attacker to have access to ZooKeeper.

CVSS severity8.8
High
EPSS probability2.24%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Unsafe deserialization in affected Apache Hadoop YARN releases allows remote authenticated users to execute commands as the YARN user. ZKConfigurationStore passes scheduler data read from ZooKeeper to ObjectInputStream without restricting deserialized classes, enabling gadget-chain execution. Exposure requires CapacityScheduler to use the optional ZooKeeper-backed configuration store and the attacker to have access to ZooKeeper.

The record

CVE
CVE-2021-25642
Published
Aug 25, 2022
Updated
Aug 3, 2024
Vendor
The Apache Software Foundation
Product
Apache Hadoop
Classifications
CWE-502, T1210
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Aug 25, 2022CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=2.9.0 to 2.10.1, 3.0.0-alpha1 to 3.1.4, 3.2.0 to 3.2.3, and 3.3.0 to 3.3.3

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

The Apache Software Foundation · Apache Hadoopversion=2.9.0 to 2.10.1, 3.0.0-alpha1 to 3.1.4, 3.2.0 to 3.2.3, and 3.3.0 to 3.3.3

Published CVSS scores

8.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-502Deserialization of Untrusted Data
T1210Exploitation of Remote Services

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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