ChainsawApplication · Apache
CVE-2020-9493
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedA deserialization flaw was found in Apache Chainsaw versions prior to 2.1.0 which could lead to malicious code execution.
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysis · moderate confidenceA deserialization vulnerability exists in Apache Chainsaw versions prior to 2.1.0. The flaw allows attackers to deserialize untrusted data without proper validation, potentially enabling remote code execution through maliciously crafted serialized objects.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.
NVD · CPE data
ChainsawApplication
< 2.1.0
Log4jFramework / library
>= 1.2, < 2.0< 1.2.18.1CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Network
- Complexity
- Low
- Privileges
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.
dbcve checksWork through these to decide whether this CVE applies to you.
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Locate Apache Chainsaw installationSearch for chainsaw*.jar files in application directories, lib folders, or common installation paths like /opt and /usr/shareAffected if Chainsaw is present and version is below 2.1.0
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Locate Apache Log4j 1.x usageSearch for log4j-1*.jar files or log4j dependencies in the application classpath, WAR files, or Maven/Gradle dependenciesAffected if Log4j 1.x (version 1.2 to 1.x) is present and the application deserializes untrusted data
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Locate Qos Reload4j usageSearch for reload4j*.jar files or reload4j references in application dependencies, lib directories, or runtime classpathAffected if Reload4j is present and version is below 1.2.18.1
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Verify deserialization of untrusted data is enabledInspect application configuration files and source code for deserialization endpoints, Java ObjectInputStream usage, or network listeners that accept serialized objects from external sourcesAffected if The application deserializes data from untrusted or remote sources without validation
You are affected if any of these products are present below the specified version thresholds AND the application is configured to deserialize untrusted data from network sources or external inputs.
Generated from the published advisory. Verify against your own configuration.
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
dbcve · scoped1.2.18.12.02.1.0
Upgrade Apache Chainsaw to version 2.1.0 or later. If upgrading is not immediately possible, restrict network access to the application and disable any deserialization of untrusted data sources.
Chainsaw 2.1.0 (or migrate to Log4j 2.x); Reload4j 1.2.18.1; or migrate from Log4j 1.x to Log4j 2.x
- 1. Identify which logging framework is in use: Apache Chainsaw, Log4j 1.x, or reload4j
- 2. For Apache Chainsaw users: Download and install version 2.1.0 or later from the Apache Log4j downloads
- 3. For Log4j 1.x users: Migrate to Log4j 2.x (recommended) or replace Log4j 1.x with reload4j version 1.2.18.1 or later
- 4. For reload4j users: Upgrade to version 1.2.18.1 or later from the reload4j project
- 5. Verify the upgrade by checking the version of the JAR file in your application classpath
- 6. Test the application to ensure logging functionality works correctly after the upgrade
Generated from the published advisory — verify against the referenced sources before acting.
Fix this in Chainsaw
Scoped from the published advisory
- Consultation2.0 h
- Implementation1.0 h
- Testing2.0 h
- Review / QA1.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $1,696.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2020-9493 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2020-9493 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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- Version or environment caveats, and links to real fixes
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