How severe is CVE-2021-32706?

CVE-2021-32706 has a CVSS 3.x base score of 7.6, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability high.

Is CVE-2021-32706 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 60% (99th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-32706?

CVE-2021-32706 affects Pi-hole. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-32706?

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

When was CVE-2021-32706 published?

CVE-2021-32706 was published on 2021-08-04 and last updated on 2026-06-17.

CVE-2021-32706

CVE-2021-32706 is a high-severity vulnerability in Pi-hole with a CVSS 3.x base score of 7.6. Its EPSS exploit-prediction score of 60% places it in the 99th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-94.

Key facts

Severity: High (CVSS 3.x base score 7.6)
CVSS v2: 6.5
EPSS exploit prediction: 60% (99th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-94
Affected product: Pi-hole
Published: 2021-08-04
Last modified: 2026-06-17

Description

Pi-hole's Web interface provides a central location to manage a Pi-hole instance and review performance statistics. Prior to Pi-hole Web interface version 5.5.1, the `validDomainWildcard` preg_match filter allows a malicious character through that can be used to execute code, list directories, and overwrite sensitive files. The issue lies in the fact that one of the periods is not escaped, allowing any character to be used in its place. A patch for this vulnerability was released in version 5.5.1.

Frequently asked questions

What is CVE-2021-32706?: Pi-hole's Web interface provides a central location to manage a Pi-hole instance and review performance statistics. Prior to Pi-hole Web interface version 5.5.1, the `validDomainWildcard` preg_match filter allows a malicious character through that can be used to execute code, list directories, and overwrite sensitive files. The issue lies in the fact that one of the periods is not escaped, allowing any character to be used in its place. A patch for this vulnerability was released in version 5.5.1.
How severe is CVE-2021-32706?: CVE-2021-32706 has a CVSS 3.x base score of 7.6, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability high.
Is CVE-2021-32706 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 60% (99th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-32706?: CVE-2021-32706 affects Pi-hole. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-32706?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-32706 published?: CVE-2021-32706 was published on 2021-08-04 and last updated on 2026-06-17.

References

Affected products (1)

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

More vulnerabilities in Pi-hole

CVE-2025-34087 — High (CVSS 8.8): An authenticated command injection vulnerability exists in Pi-hole versions up to 3.3. When adding a domain to the…
CVE-2020-11108 — High (CVSS 8.8): The Gravity updater in Pi-hole through 4.4 allows an authenticated adversary to upload arbitrary files. This can be…
CVE-2019-13051 — High (CVSS 8.8): Pi-Hole 4.3 allows Command Injection.
CVE-2024-34361 — High (CVSS 8.5): Pi-hole is a DNS sinkhole that protects devices from unwanted content without installing any client-side software. A…
CVE-2020-14162 — High (CVSS 7.8): An issue was discovered in Pi-Hole through 5.0. The local www-data user has sudo privileges to execute the pihole core…
CVE-2020-12620 — High (CVSS 7.8): Pi-hole 4.4 allows a user able to write to /etc/pihole/dns-servers.conf to escalate privileges through command…

All CVEs affecting Pi-hole →

Other CWE-94 (Code Injection) vulnerabilities

CVE-2026-57624 — Critical (CVSS 10.0): Unauthenticated Remote Code Execution (RCE) in Blocksy Companion Pro <= 2.1.46 versions.
CVE-2026-10134 — Critical (CVSS 10.0): IBM Langflow OSS 1.0.0 through 1.9.3 allows an attacker to read every secret available to the Langflow process, read…
CVE-2026-53576 — Critical (CVSS 10.0): Kestra is an open-source, event-driven orchestration platform. Prior to 1.0.45 and 1.3.21, the authentication filter…
CVE-2026-10561 — Critical (CVSS 10.0): IBM Langflow OSS 1.0.0 through 1.9.3 has an vulnerability due to an improper isolation of Python execution combined…
CVE-2026-25470 — Critical (CVSS 10.0): Improper Control of Generation of Code ('Code Injection') vulnerability in ACPT ACPT (Pro) - Custom Post Types Plugin…
CVE-2026-48836 — Critical (CVSS 10.0): Unauthenticated Remote Code Execution (RCE) in Easy Invoice <= 2.1.19 versions.

Browse all CWE-94 (Code Injection) vulnerabilities →