CVE-2026-84003 HIGH

CVE-2026-84003: Microsoft Authentication Library (MSAL) for Node.js Spoofing Vulnerability

Vendor Microsoft

Product Microsoft Authentication Library

Weakness CWE-294

Published September 8, 2026

Last update September 29, 2026

View on NVD All CVEs

CVSS base score

7.4/10

Attack vector Network

Attack complexity High

Privileges required None

User interaction None

Confidentiality High

Integrity High

CVSS vector

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N/E:U/RL:O/RC:C

What the vulnerability does

01Description

Authentication bypass by capture-replay in Microsoft Authentication Library (MSAL) for Node.js allows an unauthorized attacker to perform spoofing over a network.

Key dates

02Disclosure timeline

September 8, 2026 CVE published

September 29, 2026 Record updated

External resources

03References

NVD — National Vulnerability Database https://nvd.nist.gov/vuln/detail/CVE-2026-84003 CWE — Common Weakness Enumeration https://cwe.mitre.org/data/definitions/294.html AskarLabs — CWE-294 write-up Authentication Bypass by Capture-replay

Related vulnerabilities

Identifiers

CVE CVE-2026-84003

CWE CWE-294

CVSS 7.4 / HIGH

Affected versions