JWT Algorithm Confusion Authentication Bypass in Apache APISIX jwt-auth Plugin
CVE-2026-39999 is an authentication bypass vulnerability in Apache APISIX affecting versions 2.2 through 3.16.0. The issue is described as an Authentication Bypass by Spoofing vulnerability and is associated with JWT algorithm confusion in certain configurations of the jwt-auth plugin. Under vulnerable configurations, an attacker can spoof authentication and completely bypass the authentication checks enforced by the plugin, allowing requests to be treated as authenticated without possessing valid credentials or a legitimately accepted JWT.
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Impact, mitigation & remediation
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Impact
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Mitigation
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Remediation
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Exploits
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No public exploit code observed for this vulnerability.
Affected products & vendors
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Recent activity
6 sources tracked across advisories and community write-ups. News coverage will land here when it surfaces.
No news coverage yet. Advisories and community discussion only.
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Cross-references every affected SKU, including bundled OEM variants.
Community discussion across Reddit, Mastodon, and other social sources.