CVE-2026-48159: use-reducer-async is a React useReducer with async actions

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CRITICAL 9.3REMOTE

CVE-2026-48159 is a critical-severity flaw (CVSS 9.3) affecting affected software. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

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, a

Why this priority

Critical severity
CISA SSVC: automatable with total technical impact
Remotely exploitable, no login, no user action

A fixed release or distro patch exists.

Risk facts

CVSS score	9.3 (Critical)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	None
EPSS exploit chance	0.7% (top 49%)
CISA exploited list	No
Weakness	CWE-506
Published	2026-08-10
Last modified	2026-10-23

Publisher (CNA): GitHub, Inc.

Last updated 2026-10-23 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Timeline

2026-08-10 18:17 UTCPublished CVE record published
2026-10-23 20:10 UTCUpdated Record last modified

Exact fixes by distribution

Fedora 46 · clementine · FIXED · 1.4.2-1.fc46 · FEDORA-2026-3e748ef4d3 · source

sudo dnf upgrade --advisory=FEDORA-2026-3e748ef4d3

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2026-48159?

No fixed release is listed yet. Watch the vendor advisory and apply any mitigation shown on this page.

Is CVE-2026-48159 being exploited?

CVE-2026-48159 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2026-48159 affect?

CVE-2026-48159 affects affected software. Severity is critical (CVSS 9.3). 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 df07d5711458d8b46e11dd7afaaa21e

How urgent is CVE-2026-48159?

Priority 53/100. Critical severity; CISA SSVC: automatable with total technical impact; Remotely exploitable, no login, no user action

Software pages

React vulnerabilities

References

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