# CVE-2026-48159

## Summary

- **CVE ID:** CVE-2026-48159
- **Severity:** CRITICAL
- **CVSS Score:** 9.3 (CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N)
- **CWE:** CWE-506
- **Published:** Aug 10, 2026
- **Last Modified:** Aug 11, 2026

## Description

use-reducer-async is a React useReducer with async actions. Between 2026-05-18 16:29:52 and 2026-05-19 15:26:07, the default branch contained malicious commits da72edbde5705efcec6c62e0a3dcb73687b78dc8 through df07d5711458d8b46e11dd7afaaa21e88cafabfb that executed remote attacker-controlled code on developer machines during `npm install`. The commits were removed by force-push, but local clones, forks, and direct-SHA URLs may still contain them, and `npm install` against an affected checkout will still execute the code today. The package was not published to npm. `src/install.js` was added and wired into the `postinstall` script. It fetched a JavaScript payload from an attacker-controlled HTTPS endpoint (configurable via an environment variable), disabled TLS verification, and evaluated the response as code with `require` available. Execution was deliberately skipped on CI and cloud/serverless environments, targeting developer workstations. The second-stage payload was attacker-hosted and cannot be reconstructed. Assume full compromise of anything reachable from a Node process with the user's permissions. Those who ran `npm install` against an affected checkout on a developer machine on or after 2026-05-18 16:29:52 should treat the machine as compromised, rotate every credential the machine could reach, audit account activity since 2026-05-18 16:29:52, and clean local clones.

## Affected Products

- dai-shi — use-reducer-async (>= da72edbde5705efcec6c62e0a3dcb73687b78dc8, <= df07d5711458d8b46e11dd7afaaa21e88cafabfb)

## References

- [CNA](https://github.com/dai-shi/use-reducer-async/security/advisories/GHSA-2786-p4vj-vx8x)

## Exploitation Prediction (EPSS)

- **EPSS Score:** 0.49%
- **EPSS Percentile:** 40.5

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_Exported from OnDuty AI Vulnerability Intelligence on 2026-09-10._