CVE-2026-39998

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.

CVSS v3 8.8 HIGH

8.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://lists.apache.org/thread/vgkvy396010d7g6m0jrn4d3hjf2svlvv	Vendor Advisory Mailing List
http://www.openwall.com/lists/oss-security/2026/06/19/4	Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:apache:apisix:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-06-19 14:16

Updated : 2026-06-23 14:57

NVD link : CVE-2026-39998

Mitre link : CVE-2026-39998

CVE.ORG link : CVE-2026-39998

JSON object : View

Products Affected

apache

apisix

CWE

CWE-20

Improper Input Validation

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