Security readout for executives and security teams
Plain-English summary
Pi-hole’s web admin interface before version 5.5.1 had an authenticated remote code execution flaw. A logged-in attacker could abuse improper domain wildcard validation to run code and affect files on the Pi-hole system. The main business concern is compromise or disruption of DNS filtering infrastructure.
Executive priority
Treat this as a high-priority infrastructure patch, especially for Pi-hole systems reachable beyond a tightly controlled admin network. The issue can affect DNS service availability and host integrity if an authenticated attacker gains access.
Technical view
CVE-2021-32706 affects Pi-hole AdminLTE before 5.5.1. The validDomainWildcard preg_match filter did not escape one period, allowing an unexpected character through. The advisory states this could enable code execution, directory listing, and overwriting sensitive files. CVSS 3.1 is 7.6 with network access, low complexity, and low privileges required.
Likely exposure
Exposure is limited to Pi-hole deployments running the Web interface/AdminLTE before 5.5.1 where an attacker can authenticate to the admin interface. Internet-exposed or broadly reachable admin portals increase practical risk.
Exploitation context
The CVE is not listed as CISA KEV in the provided bundle, and no cited source confirms active exploitation. The risk remains material because exploitation requires only authenticated web access, no user interaction, and low attack complexity.
Researcher notes
The provided sources support the affected product, version boundary, root cause, CVSS vector, and fixed release. They do not provide public exploit evidence, detailed indicators, or additional supported mitigations beyond upgrading to 5.5.1.
Mitigation direction
- Upgrade Pi-hole Web interface/AdminLTE to version 5.5.1 or later.
- Identify and prioritize any externally reachable Pi-hole admin interfaces.
- Restrict admin interface access to trusted networks or VPN while patching.
- Review Pi-hole vendor guidance if upgrade timing or compatibility is uncertain.
- Review administrative account access and remove unnecessary users.
Validation and detection
- Inventory Pi-hole instances and record Web interface/AdminLTE versions.
- Confirm every affected instance is upgraded to 5.5.1 or later.
- Check whether admin interfaces are reachable from untrusted networks.
- Review authenticated web-interface activity for unexpected administrative changes.
- Document patch status, exposure, and any compensating access controls.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-94: Code execution behavior lookup
Code execution and unsafe deserialization weaknesses often justify reviewing execution behavior and process telemetry. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupExecution behavior lookup
The CVE wording references code or command execution, so execution technique review may help defensive triage. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2021-32706 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- High
- CVSS
- 7.6 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:H
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:H2.84.7Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
7.6HighVector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:H
Source materials
- CVE List V5 sourceCVE List V5
- https://github.com/pi-hole/AdminLTE/security/advisories/GHSA-5cm9-6p3m-v259CVE reference · x_refsource_CONFIRM
- https://github.com/pi-hole/AdminLTE/releases/tag/v5.5.1CVE reference · x_refsource_MISC
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Improper Control of Generation of Code ('Code Injection')
Improper Control of Generation of Code ('Code Injection') represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.