CVE-2026-48158: use-context-selector is a React useContextSelector hook in userland Between 2026-05-18 15:57:18 and 2026-05-19 15:24:34, the default branch contained ...

Description

use-context-selector is a React useContextSelector hook in userland Between 2026-05-18 15:57:18 and 2026-05-19 15:24:34, the default branch contained malicious commits 9d8481a513b7b0d1c0941b220c69b25de748641b through 6f2dae054ca014068bdbbb4db96006424d674124 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 15:57:18 should treat the machine as compromised, rotate every credential the machine could reach, audit account activity** since 2026-05-18 15:57:18, and clean local clones.

Metrics

CVSS 4.0

9.3/10

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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Weakness Enumeration

CWE-506

Affected Software

Source: CNA advisory (CVE.org). NVD analysis pending.

Vendor	Product	Versions
dai-shi	use-context-selector	>= 9d8481a513b7b0d1c0941b220c69b25de748641b, <= 6f2dae054ca014068bdbbb4db96006424d674124

References

https://github.com/dai-shi/use-context-selector/security/advisories/GHSA-7h6v-mwq6-jhm8

Timeline

Published: Aug 10, 2026
Last Modified: Aug 11, 2026
Status: Received

Frequently Asked Questions

What is CVE-2026-48158?

use-context-selector is a React useContextSelector hook in userland Between 2026-05-18 15:57:18 and 2026-05-19 15:24:34, the default branch contained malicious commits 9d8481a513b7b0d1c0941b220c69b25de748641b through 6f2dae054ca014068bdbbb4db96006424d674124 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 15:57:18 should treat the machine as compromised, rotate every credential the machine could reach, audit account activity** since 2026-05-18 15:57:18, and clean local clones.

How severe is CVE-2026-48158?

CVE-2026-48158 has a CVSS score of 9.3/10 (CRITICAL severity).

How do I fix CVE-2026-48158?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

How Strix Helps

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