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 vulnerability arises from the forward-auth plugin's handling of identity headers, which can be spoofed by an attacker when specific configurations are used. This could allow unauthorized identity spoofing within the system. The Apache Software Foundation has addressed this issue in version 3.17.0.
Potential Impact
An attacker exploiting this vulnerability can spoof identity headers in Apache APISIX when the forward-auth plugin is configured in a certain way. This could lead to unauthorized access or impersonation within systems relying on these headers for authentication or authorization decisions. The CVSS 4.0 score of 5.8 indicates a medium impact with network attack vector, low attack complexity, and partial privileges required.
Mitigation Recommendations
Users should upgrade Apache APISIX to version 3.17.0 or later, where this vulnerability is fixed. No other official remediation or temporary fixes are documented. Patch status is not explicitly confirmed in the advisory, but the vendor recommends upgrading to 3.17.0 to resolve the issue.
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 vulnerability arises from the forward-auth plugin's handling of identity headers, which can be spoofed by an attacker when specific configurations are used. This could allow unauthorized identity spoofing within the system. The Apache Software Foundation has addressed this issue in version 3.17.0.
Potential Impact
An attacker exploiting this vulnerability can spoof identity headers in Apache APISIX when the forward-auth plugin is configured in a certain way. This could lead to unauthorized access or impersonation within systems relying on these headers for authentication or authorization decisions. The CVSS 4.0 score of 5.8 indicates a medium impact with network attack vector, low attack complexity, and partial privileges required.
Mitigation Recommendations
Users should upgrade Apache APISIX to version 3.17.0 or later, where this vulnerability is fixed. No other official remediation or temporary fixes are documented. Patch status is not explicitly confirmed in the advisory, but the vendor recommends upgrading to 3.17.0 to resolve the issue.
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: 6/19/2026, 2:05:51 PM
Last enriched: 6/19/2026, 2:21:42 PM
Last updated: 6/19/2026, 10:57:21 PM
Views: 11
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