CVE-2020-9493Network attack vector

Remote code execution via serialized log events

Published Jun 16, 2021 · Updated Aug 4, 2024

Deserialization in Apache Chainsaw before 2.1.0 allows remote attackers to execute arbitrary code through malicious serialized log events. The serialized-event receiver accepts network-supplied Java objects and deserializes them without enforcing a safe class restriction. Exposure requires Chainsaw to be configured to read serialized log events; successful exploitation runs code in the application's process context.

CVSS severity9.8
Critical
EPSS probability4.59%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Deserialization in Apache Chainsaw before 2.1.0 allows remote attackers to execute arbitrary code through malicious serialized log events. The serialized-event receiver accepts network-supplied Java objects and deserializes them without enforcing a safe class restriction. Exposure requires Chainsaw to be configured to read serialized log events; successful exploitation runs code in the application's process context.

The record

CVE
CVE-2020-9493
Published
Jun 16, 2021
Updated
Aug 4, 2024
Vendor
The Apache Software Foundation
Product
Apache Chainsaw
Classifications
CWE-502, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 16, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

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

  1. Affected versionversion=Apache Chainsaw <2.1.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

The Apache Software Foundation · Apache Chainsawversion=Apache Chainsaw <2.1.0

Published CVSS scores

6.8NIST NVDAV:N/AC:M/Au:N/C:P/I:P/A:P
9.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/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
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-502Deserialization of Untrusted Data
T1190Exploit Public-Facing Application

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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