Authenticated code execution via malicious add-on upload
Published Jan 13, 2022 · Updated Jul 9, 2026
Command execution in JPress 4.2.0 allows remote authenticated users to run arbitrary commands by installing a malicious add-on. _AddonController.doUploadAndInstall accepts an uploaded add-on JAR, installs it, and loads its classes through a new class loader without establishing that the code is trusted. Administrative access to the back end is required; the published procedure uses a weak password, registers a controller from the JAR, and invokes it through an HTTP request.
Summary
What happened
Command execution in JPress 4.2.0 allows remote authenticated users to run arbitrary commands by installing a malicious add-on. _AddonController.doUploadAndInstall accepts an uploaded add-on JAR, installs it, and loads its classes through a new class loader without establishing that the code is trusted. Administrative access to the back end is required; the published procedure uses a weak password, registers a controller from the JAR, and invokes it through an HTTP request.
The record
- CVE
- CVE-2021-45807
- Published
- Jan 13, 2022
- Updated
- Jul 9, 2026
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- T1505.003
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Jan 13, 2022CVE publishedPublication date reported by the CVE source.
- Jul 9, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
What conditions does exploitation require?
What is affected?
Affected products and versions are unavailable in this record.
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.
Weakness, pattern, technique
Public exploit references
- Malicious JPress add-on command-execution procedureproof of concept · demonstrated
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Technologies
Your stack
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Your stack
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