CVE-2026-39998: CWE-20 Improper Input Validation in Apache Software Foundation Apache APISIX
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.
AI Analysis
Technical Summary
CVE-2026-39998 is an improper input validation vulnerability (CWE-20) in Apache APISIX affecting versions 2.12.0 through 3.16.0. The flaw exists in the forward-auth plugin configuration, enabling an attacker with some privileges to spoof identity headers by exploiting insufficient validation. The issue is fixed in Apache APISIX version 3.17.0.
Potential Impact
An attacker can exploit this vulnerability to spoof identity headers, potentially bypassing authentication or authorization controls depending on the forward-auth plugin configuration. This could lead to unauthorized access or privilege escalation within affected deployments.
Mitigation Recommendations
Users should upgrade Apache APISIX to version 3.17.0 or later, where this vulnerability is fixed. No other mitigations or temporary workarounds are indicated in the available data.
CVE-2026-39998: CWE-20 Improper Input Validation in Apache Software Foundation Apache APISIX
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 v4.0
Score 5.8medium
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-39998 is an improper input validation vulnerability (CWE-20) in Apache APISIX affecting versions 2.12.0 through 3.16.0. The flaw exists in the forward-auth plugin configuration, enabling an attacker with some privileges to spoof identity headers by exploiting insufficient validation. The issue is fixed in Apache APISIX version 3.17.0.
Potential Impact
An attacker can exploit this vulnerability to spoof identity headers, potentially bypassing authentication or authorization controls depending on the forward-auth plugin configuration. This could lead to unauthorized access or privilege escalation within affected deployments.
Mitigation Recommendations
Users should upgrade Apache APISIX to version 3.17.0 or later, where this vulnerability is fixed. No other mitigations or temporary workarounds are indicated in the available data.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- apache
- Date Reserved
- 2026-04-08T02:34:21.516Z
- Cvss Version
- 4.0
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a354cbff198dc38c1587388
Added to database: 06/19/2026, 14:05:51 UTC
Last enriched: 06/26/2026, 15:14:40 UTC
Last updated: 08/03/2026, 07:17:56 UTC
Views: 123
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