TryGhost up to 6.19.x File Extension Filter encoding error

CVSS Meta Temp Score
CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.
Current Exploit Price (≈)
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CTI Interest Score
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5.2$0-$5k0.79+

Summaryinfo

A vulnerability was found in TryGhost Ghost up to 6.19.x. It has been classified as problematic. This vulnerability affects unknown code of the component File Extension Filter. The manipulation leads to encoding error. This vulnerability is listed as CVE-2026-103276. The attack may be initiated remotely. There is no available exploit. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability was found in TryGhost Ghost up to 6.19.x. It has been rated as problematic. This issue affects an unknown code block of the component File Extension Filter. The manipulation with an unknown input leads to a encoding error vulnerability. Using CWE to declare the problem leads to CWE-172. The product does not properly encode or decode the data, resulting in unexpected values. Impacted is confidentiality. The summary by CVE 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 advisory is shared at github.com. The identification of this vulnerability is CVE-2026-103276 since 09/30/2026. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. Neither technical details nor an exploit are publicly available.

Upgrading to version 6.20.0 eliminates this vulnerability.

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

Vendor

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 5.3
VulDB Meta Temp Score: 5.2

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 5.3
CNA Vector (VulnCheck): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Encoding error
CWE: CWE-172
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Ghost 6.20.0

Timelineinfo

09/30/2026 CVE reserved
10/01/2026 +1 days Advisory disclosed
10/01/2026 +0 days VulDB entry created
10/01/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-103276 (🔒)
GCVE (CVE): GCVE-0-2026-103276
GCVE (VulDB): GCVE-100-412613

Entryinfo

Created: 10/01/2026 13:22
Changes: 10/01/2026 13:22 (76)
Complete: 🔍
Cache ID: 216::103

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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