8.8

CVE-2026-39998: apache software foundation apache apisix Improper Input Validation

CVSS: 8.8v3.1HighAnalyzed
Published 19-06-2026Last modified 22-06-2026
Open JSON

Vulnerability summary

CVE-2026-39998 is a high (CVSS 8.8) Improper Input Validation vulnerability in apache software foundation apache apisix. EPSS estimates a 0.68% chance of exploitation in the next 30 days, higher than 51.2% of scored vulnerabilities.

Overall risk
35/100
0100
Medium · default modelHow is this calculated?
CVSS score
8.8/10
010
High · v3.1 (NVD)
EPSS score
0.68%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 19-06-2026
    PublishedVulnerability first disclosed.
  2. 22-06-2026
    Last modifiedVulnerability information updated.

Description

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 metrics

3 scores · 2 sources · 2 versions

EPSS trend

Probability

0.68%

Chance of exploitation in the next 30 days

Percentile

51%

Versus all other CVEs

30-day change

0.00 pp

From 0.68% on 18-09-2026

18-09-202618-10-2026
EPSS score
0.68%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Apache1 product
Apache software foundation1 product

2 vendors · 2 products

References

2 links