Pi-hole 5.0, 5.1, and 5.1.1 allows XSS via the Options header to the admin/ URI. A remote user is able to inject arbitrary web script or HTML due to incorrect sanitization of user-supplied data and achieve a Reflected Cross-Site Scripting attack against other users and steal the session cookie.
CVSS v4.0 Metrics
Exploitability
Attack VectorNetwork
ComplexityLow
RequirementsPresent
PrivilegesLow
User InteractionActive
Threat
Exploit MaturityUnreported
Vulnerable System
ConfidentialityLow
IntegrityLow
AvailabilityNone
Subsequent System
ConfidentialityNone
IntegrityNone
AvailabilityNone
Supplemental
SafetyNegligible
AutomatableYes
RecoveryAutomatic
Value DensityConcentrated
UrgencyMedium
Change Log
| Date | Source | Changes | Score |
|---|
| 2026-07-21 | nvd | AV: P→N, AC: H→L, PR: H→L, VC: N→L, VI: N→L | 0.0 → 0.4 |
| 2026-07-21 | cve.org | initial, patch: Unavailable | 0.0 |
Affected Software
| Vendor | Product | Version |
|---|
| pi-hole | pi-hole | 5.0 |
| pi-hole | pi-hole | 5.1 |
| pi-hole | pi-hole | 5.1.1 |
Published: 2021-02-18
