What is CVE-2026-39999?

CVE-2026-39999 is a critical-severity vulnerability in Apache Apisix, classified under Authentication Bypass by Spoofing. CVSS score: 9.1/10. Published 2026-06-19.

How severe is CVE-2026-39999?

Critical severity. CVSS v3 base score is 9.1 out of 10.

Vulnerability in Apache Apisix

CVE-2026-39999

Authentication Bypass by Spoofing vulnerability in Apache APISIX. The attacker can completely bypass authentication capitalising on certain configurations of jwt-auth plugin. This issue affects Apache APISIX: from v2.2 through v3.16.0. Users are recommended to upgrade to version v3.17.0, which fixes the issue.

Published 2026-06-19 · last modified 2026-06-23.

CVSS v3 metric

CVSS v3 base score 9.1 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N.

EPSS exploit prediction

EPSS: 0.006 (48.4th percentile), scored 2026-09-29.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 48th percentile — 48.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.006 · newest: 0.006 · change: 0.000

Affected products

Apache Apisix
Apache Software Foundation Apisix — versions 2.2

Weakness classification (CWE)

CWE-290 — Authentication Bypass by Spoofing

References

lists.apache.org/thread/nfopt8cnxd3k0rs1oxtr7lzxrdw4mojq (vendor-advisory, Mailing List, Vendor Advisory)
af854a3a-2127-422b-91ae-364da2661108 (Third Party Advisory)

Frequently asked questions

What is CVE-2026-39999?: CVE-2026-39999 is a critical-severity vulnerability in Apache Apisix, classified under Authentication Bypass by Spoofing. CVSS score: 9.1/10. Published 2026-06-19.
How severe is CVE-2026-39999?: Critical severity. CVSS v3 base score is 9.1 out of 10.