How severe is CVE-2026-31908?

CVE-2026-31908 has a CVSS 3.x base score of 9.1, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.

Is CVE-2026-31908 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (40th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-31908?

CVE-2026-31908 affects Apache Apisix. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-31908?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

Does CVE-2026-31908 have an EU (EUVD) identifier?

Yes. CVE-2026-31908 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-22225.

When was CVE-2026-31908 published?

CVE-2026-31908 was published on 2026-04-14 and last updated on 2026-06-17.

CVE-2026-31908

CVE-2026-31908 is a critical-severity vulnerability in Apache Apisix with a CVSS 3.x base score of 9.1. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-75.

Key facts

Severity: Critical (CVSS 3.x base score 9.1)
EPSS exploit prediction: 1% (40th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-22225
Weakness: CWE-75
Affected product: Apache Apisix
Published: 2026-04-14
Last modified: 2026-06-17

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.

Frequently asked questions

What is CVE-2026-31908?: 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.
How severe is CVE-2026-31908?: CVE-2026-31908 has a CVSS 3.x base score of 9.1, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.
Is CVE-2026-31908 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (40th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-31908?: CVE-2026-31908 affects Apache Apisix. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-31908?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
Does CVE-2026-31908 have an EU (EUVD) identifier?: Yes. CVE-2026-31908 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-22225.
When was CVE-2026-31908 published?: CVE-2026-31908 was published on 2026-04-14 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:apache:apisix:*:*:*:*:*:*:*:*

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