CVE-2026-33376 (CVSS 7.4)

Description

When using an IPv6 allow-list for the Auth Proxy feature, it defaults to /32 addresses. Addresses specifying a mask explicitly are not affected; to mitigate easily, add the desired mask (usually /128) to the addresses. Only auth proxy is affected; Okta, SAML, LDAP, etc are unaffected here.

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CVSS v3.1 Score

7.4

HIGH

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N

EPSS — Exploit Prediction

0.0002

Probability of exploitation

0.05%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-1188 CWE-1188

References

Other References

https://grafana.com/security/security-advisories/cve-2026-33376

Frequently Asked Questions

What is CVE-2026-33376? +

When using an IPv6 allow-list for the Auth Proxy feature, it defaults to /32 addresses. Addresses specifying a mask explicitly are not affected; to mitigate easily, add the desired mask (usually /128) to the addresses. Only auth proxy is affected; Okta, SAML, LDAP, etc are unaffected here. It has a CVSS v3.1 base score of 7.4 (HIGH).

How severe is CVE-2026-33376? +

CVE-2026-33376 has a CVSS v3.1 score of 7.4 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching. The EPSS score is 0.0002, placing it in the 0th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2026-33376? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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CVE-2026-33376