Code execution via malicious postinstall payload
Published Aug 10, 2026 · Updated Aug 10, 2026
Embedded malicious code in affected use-reducer-async commits allows remote attackers to execute code during npm install on developer machines. The added src/install.js postinstall hook disables TLS verification, fetches JavaScript from an attacker-controlled HTTPS endpoint, and evaluates it with require access. Execution requires npm install against an affected checkout on a developer workstation; the resulting Node process can access data and credentials available to that user.
Summary
What happened
Embedded malicious code in affected use-reducer-async commits allows remote attackers to execute code during npm install on developer machines. The added src/install.js postinstall hook disables TLS verification, fetches JavaScript from an attacker-controlled HTTPS endpoint, and evaluates it with require access. Execution requires npm install against an affected checkout on a developer workstation; the resulting Node process can access data and credentials available to that user.
The record
- CVE
- CVE-2026-48159
- Published
- Aug 10, 2026
- Updated
- Aug 10, 2026
- Vendor
- Daishi Kato
- Product
- use-reducer-async
- Classifications
- CWE-506, T1195.001
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Aug 10, 2026CVE publishedPublication date reported by the CVE source.
- Aug 10, 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?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=>= da72edbde5705efcec6c62e0a3dcb73687b78dc8, <= df07d5711458d8b46e11dd7afaaa21e88cafabfb
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
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Weakness, pattern, technique
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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