How severe is CVE-2026-33406?

CVE-2026-33406 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2026-33406 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (17th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-33406?

CVE-2026-33406 affects Pi-hole Web Interface. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-33406?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2026-33406 have an EU (EUVD) identifier?

Yes. CVE-2026-33406 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-19285.

When was CVE-2026-33406 published?

CVE-2026-33406 was published on 2026-04-06 and last updated on 2026-06-17.

CVE-2026-33406

CVE-2026-33406 is a medium-severity vulnerability in Pi-hole Web Interface with a CVSS 3.x base score of 5.4. 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-79.

Key facts

Severity: Medium (CVSS 3.x base score 5.4)
EPSS exploit prediction: 0% (17th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-19285
Weakness: CWE-79
Affected product: Pi-hole Web Interface
Published: 2026-04-06
Last modified: 2026-06-17

Description

Pi-hole Admin Interface is a web interface for managing Pi-hole, a network-level ad and internet tracker blocking application. From 6.0 to before 6.5, configuration values from the /api/config endpoint are placed directly into HTML value="" attributes without escaping in settings-advanced.js, enabling HTML attribute injection. A double quote in any config value breaks out of the attribute context. JavaScript execution is blocked by the server's CSP (script-src 'self'), but injected attributes can alter element styling for UI redressing. The primary attack vector is importing a malicious teleporter backup, which bypasses per-field server-side validation. This vulnerability is fixed in 6.5.

Frequently asked questions

What is CVE-2026-33406?: Pi-hole Admin Interface is a web interface for managing Pi-hole, a network-level ad and internet tracker blocking application. From 6.0 to before 6.5, configuration values from the /api/config endpoint are placed directly into HTML value="" attributes without escaping in settings-advanced.js, enabling HTML attribute injection. A double quote in any config value breaks out of the attribute context. JavaScript execution is blocked by the server's CSP (script-src 'self'), but injected attributes can alter element styling for UI redressing. The primary attack vector is importing a malicious teleporter backup, which bypasses per-field server-side validation. This vulnerability is fixed in 6.5.
How severe is CVE-2026-33406?: CVE-2026-33406 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2026-33406 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (17th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-33406?: CVE-2026-33406 affects Pi-hole Web Interface. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-33406?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-33406 have an EU (EUVD) identifier?: Yes. CVE-2026-33406 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-19285.
When was CVE-2026-33406 published?: CVE-2026-33406 was published on 2026-04-06 and last updated on 2026-06-17.

References

https://github.com/pi-hole/web/security/advisories/GHSA-9rfm-c5g6-538p

Affected products (1)

cpe:2.3:a:pi-hole:web_interface:*:*:*:*:*:*:*:*

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