CVE-2026-103276

EUVD-2026-90669
Ghost versions before 6.20.0 contain a file extension filtering bypass vulnerability that allows unauthenticated attackers to read theme templates and metadata. Attackers can use URL encoding to bypass extension validation and access sensitive theme files.
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
NISTPrimary
5.3 MEDIUM
NETWORK
LOW
NONE
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
Awaiting analysis
This vulnerability is currently awaiting analysis.
Base Score
CVSS 3.x
EPSS Score
Percentile: Unknown
Common Weakness Enumeration
References
https://github.com/TryGhost/Ghost/security/advisories/GHSA-6v8p-3jx9-8chr
https://www.vulncheck.com/advisories/ghost-before-6.20.0-file-read-via-url-encoding-bypass