CVE-2026-39998

EUVD-2026-38011
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.
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
apacheCNA
5.8 MEDIUM
NETWORK
LOW
LOW
CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:N/SC:H/SI:H/SA:H
Base Score
CVSS 3.x
EPSS Score
Percentile: Unknown
Early Detection
Affected products identified ahead of NVD analysis through intelligence sources.
VendorProductVersionSource
apacheapisix
2.12.0 ≤
𝑥
≤ 3.16.0
CNA
Common Weakness Enumeration
References
https://lists.apache.org/thread/vgkvy396010d7g6m0jrn4d3hjf2svlvv
http://www.openwall.com/lists/oss-security/2026/06/19/4