CVE-2026-24910Public exploit

Lifecycle script execution via source-blind trust matching

Published Jan 27, 2026 · Updated Jan 27, 2026

Trust allow-list bypass in Bun before 1.3.5 allows local users to execute dependency lifecycle scripts through non-npm packages. The package manager checks only a dependency's declared name against its default trusted list, without binding trust to an npm registry source. A malicious file, link, git, or GitHub dependency must reuse a trusted name; installation then runs its lifecycle code with the installing process's privileges.

CVSS severity5.9
Medium
EPSS probability0.11%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Trust allow-list bypass in Bun before 1.3.5 allows local users to execute dependency lifecycle scripts through non-npm packages. The package manager checks only a dependency's declared name against its default trusted list, without binding trust to an npm registry source. A malicious file, link, git, or GitHub dependency must reuse a trusted name; installation then runs its lifecycle code with the installing process's privileges.

The record

CVE
CVE-2026-24910
Published
Jan 27, 2026
Updated
Jan 27, 2026
Vendor
Bun
Product
Bun
Classifications
CWE-348, T1195.001
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jan 27, 2026CVE publishedPublication date reported by the CVE source.
  2. Jan 27, 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.

  1. Affected versionversion=0 <1.3.5

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

Bun · Bunversion=0 <1.3.5

Published CVSS scores

5.9MITRECVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:C/C:N/I:H/A:N

CVSS describes severity. EPSS estimates exploitation probability.

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.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-348Use of Less Trusted Source
T1195.001Compromise Software Dependencies and Development Tools

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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