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CVE-2021-26505 — Vulnerability in hellojs — CVE Details

CRITICAL

MrSwitch hello.js vulnerable to prototype pollution

Published August 11, 2023Updated November 8, 2023Source: osv

Summary

A prototype pollution vulnerability in MrSwitch hello.js prior to version 1.18.8 allows remote attackers to execute arbitrary code via `hello.utils.extend` function.

Advisory Timeline

  • First published August 11, 2023 (1158 days ago).
  • Last revised November 8, 2023 — 89 days after initial publication.

Remediation

Upgrade to the fixed version using your package manager.

npm
Update hellojs to 1.18.8 or later
npm install hellojs@1.18.8

After upgrading, run your dependency scanner again to confirm the vulnerability is resolved.

Affected Packages (1)

Affects 1 ecosystem: npm (1).

PackageEcosystemAffectedFixed In
hellojs
npm
All versions1.18.8

Vulnerability Classification

Common Weakness Enumeration (CWE) identifiers for this vulnerability type.

  • CWE-1321
    Prototype PollutionMITRE

CVSS Score Breakdown

What the CVSS (Common Vulnerability Scoring System) 9.8 score means for each attack dimension.

Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

References

Frequently Asked Questions

What is CVE-2021-26505?
MrSwitch hello.js vulnerable to prototype pollution This vulnerability has been assigned a severity rating of CRITICAL (CVSS score: 9.8/10).
How do I check if my project is affected by CVE-2021-26505?
CVE-2021-26505 affects hellojs. Use GeekWala's free vulnerability scanner to check your dependencies against CVE-2021-26505 and 200,000+ other known vulnerabilities.

Severity & Exploitability

CVSS Score
9.8

Exploitation is straightforward and causes maximum impact. Patch immediately.

Also Known As

GHSA-g3vf-47fv-8f3c

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