Koen Reus Post to Google My Business Plugin up to 3.5.6 Image Validation validate_external_image_size mbp_post_attachment server-side request forgery

CVSS Meta Temp Score
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CTI Interest Score
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6.2$0-$5k0.00+

Summaryinfo

A vulnerability classified as critical was found in Koen Reus Post to Google My Business Plugin up to 3.5.6. Impacted is the function validate_external_image_size of the component Image Validation. Executing a manipulation of the argument mbp_post_attachment can lead to server-side request forgery. This vulnerability is tracked as CVE-2026-127217. The attack can be launched remotely. No exploit exists. Upgrading the affected component is advised.

Detailsinfo

A vulnerability has been found in Koen Reus Post to Google My Business Plugin up to 3.5.6 and classified as critical. This vulnerability affects the function validate_external_image_size of the component Image Validation. The manipulation of the argument mbp_post_attachment with an unknown input leads to a server-side request forgery vulnerability. The CWE definition for the vulnerability is CWE-918. The web server receives a URL or similar request from an upstream component and retrieves the contents of this URL, but it does not sufficiently ensure that the request is being sent to the expected destination. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

Post to Google My Business plugin for WordPress before 3.5.7 contains a blind server-side request forgery vulnerability that allows authenticated users with Contributor-level privileges or higher to make the server send requests to arbitrary hosts by supplying an unvalidated mbp_post_attachment URL that reaches a raw getimagesize() call in validate_external_image_size() via the preview REST route. Attackers can exploit this to perform internal port scanning, probe internal-only services and cloud metadata endpoints, and trigger GET-based side effects on internal systems, bypassing network perimeter controls since the request originates from the web server.

The advisory is shared for download at wordpress.org. This vulnerability was named CVE-2026-127217 since 11/12/2026. The exploitation appears to be easy. The attack can be initiated remotely. There are known technical details, but no exploit is available.

Upgrading to version 3.5.7 eliminates this vulnerability.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Vendor

Name

Version

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: 6.3
VulDB Meta Temp Score: 6.2

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 6.4
CNA Vector (VulnCheck): 🔒

CVSSv2info

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

Exploitinginfo

Class: Server-side request forgery
CWE: CWE-918
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: Post to Google My Business Plugin 3.5.7

Timelineinfo

11/12/2026 CVE reserved
11/13/2026 +1 days Advisory disclosed
11/13/2026 +0 days VulDB entry created
11/13/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: wordpress.org
Status: Confirmed

CNA: VulnCheck
CVE: CVE-2026-127217 (🔒)

GCVE (CVE): GCVE-0-2026-127217
GCVE (VulDB): GCVE-100-437332

Entryinfo

Created: 11/13/2026 22:29
Changes: 11/13/2026 22:29 (77)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

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