CVE-2026-39998: Apache APISIX: Identity Injection via forward-auth Plugin Missing Header Cleanup

Published Jun 19, 2026
·
Updated

Improper Input Validation vulnerability in Apache APISIX.

The attacker can take advantage of certain configuration in forward-auth plugin to spoof identity headers. This issue affects Apache APISIX: from 2.12.0 through 3.16.0.

Users are recommended to upgrade to version 3.17.0, which fixes the issue.

Affected Software

2 affected components
Apache APISIX>=2.12.0<=3.16.0
Apache APISIX>=2.12.0<3.17.0

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade Apache APISIX to a version that resolves this vulnerability.

    Fixed in 3.17.0

Event History

Jun 19, 2026
CVE Published
via MITRE·01:04 PM
Data Sourced
via MITRE·01:04 PM
DescriptionWeakness
Data Sourced
via NVD·02:16 PM
DescriptionSeverityWeaknessAffected Software
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Frequently Asked Questions

1

What is the severity of CVE-2026-39998?

CVE-2026-39998 has a severity rating of medium with a CVSS score of 5.8.

2

How do I fix CVE-2026-39998?

To fix CVE-2026-39998, users should upgrade Apache APISIX to version 3.17.0 or later.

3

What type of vulnerability is CVE-2026-39998?

CVE-2026-39998 is an improper input validation vulnerability that allows identity header spoofing.

4

Which versions of Apache APISIX are affected by CVE-2026-39998?

CVE-2026-39998 affects Apache APISIX versions from 2.12.0 through 3.16.0.

5

Can CVE-2026-39998 affect the security of my applications?

Yes, CVE-2026-39998 can compromise the security of applications by allowing attackers to spoof identity headers.

Contact

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