CVE-2026-84003 Microsoft Authentication Library (MSAL) for Node.js Spoofing Vulnerability
An attacker can bypass authentication via capture-replay attacks in MSAL for Node.js, enabling network spoofing.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-84003?
CVE-2026-84003 is a high-severity authentication bypass vulnerability in Microsoft Authentication Library, published on 8 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Authentication bypass by capture-replay in Microsoft Authentication Library (MSAL) for Node.js allows an unauthorized attacker to perform spoofing over a network.
Weakness: CWE-294
Which versions are affected by CVE-2026-84003?
It affects 1 product.
Products include Microsoft Azure\/Msal-Node.
How do I fix CVE-2026-84003?
No fix has been published for CVE-2026-84003 yet. Limit exposure of the affected software until one is available.
Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.
Is CVE-2026-84003 being exploited?
There is no known exploitation of CVE-2026-84003 in the wild and no public exploit code.
Sources
Also known as GHSA-gmqm-6r28-m87v.