Critical severity · published Apr 14, 2026
CVE-2026-31908
Apache APISIX: forward auth plugin allows header injection
9.1
CVSS
0.5%
EPSS
No
On KEV
Description
Header injection vulnerability in Apache APISIX.
The attacker can take advantage of certain configuration in forward-auth plugin to inject malicious headers.
This issue affects Apache APISIX: from 2.12.0 through 3.15.0.
Users are recommended to upgrade to version 3.16.0, which fixes the issue.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 44% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
AA
Apache APISIX · Apache Software Foundation
2.12.0 through 3.15.0 · source: vendor
AP
Apisix · Apache
2.12.0 before 3.16.0 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-31908
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-31908
Mailing List
https://lists.apache.org/thread/sob643s5lztov7x579j8o0c444t36n6b
Mailing List
http://www.openwall.com/lists/oss-security/2026/04/14/3
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