CVE-2026-103276CWE-173

CVE-2026-103276

Medium · published October 1, 2026

CVSS v3.1
5.3
EPSS
0%
Percentile
12.6
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
5.3 · MEDIUM
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
CVSS v4.0
6.9 · CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N
EPSS
0.00226 · 12.6th percentile
Weakness
CWE-173 · Improper Handling of Alternate Encoding
Published
2026-10-01T15:17Z
References (2)
https://github.com/TryGhost/Ghost/security/advisories/GHSA-6v8p-3jx9-8chr · [email protected]https://www.vulncheck.com/advisories/ghost-before-6.20.0-file-read-via-url-encoding-bypass · [email protected]
EPSS history
Timeline
  • 03 OCT 03:41Z
    EPSS moved — → 0%
    epss
  • 01 OCT 10:42Z
    Ghost before 6.20.0 File Read via URL Encoding Bypass
    cvelistv5