CVE-2026-54721

Silverstripe UserForms: Remote code execution via userforms email subject

Published: Aug 27, 2026Updated: Sep 9, 2026 Sources: CVE List NVDCWE-94

8.8HIGH

Description

Silverstripe UserForms provides a visual form builder for the Silverstripe CMS. From 6.0.0 until 6.4.9, 7.0.7, and 7.1.1, the userform email recipient subject field in the CMS accepts a specially crafted payload that can be interpreted as executable server-side code. An authenticated CMS user with permission to configure a UserForms email recipient can use the subject field to run arbitrary code on the server, compromising confidentiality, integrity, and availability. This issue is fixed in versions 6.4.9, 7.0.7, and 7.1.1.

No summary for this CVE yet.

CVSS Vector Breakdown

Exploitability

AV:NAttack Vector

Network

AC:LAttack Complexity

Low

PR:LPrivileges Required

Low

UI:NUser Interaction

None

Scope

S:UScope

Unchanged

Impact

C:HConfidentiality

High

I:HIntegrity

High

A:HAvailability

High

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Weaknesses

CWE-94

Affected Products

silverstripe

commercialaka silverstripe framework, silverstripe cms

silverstripe-userformsOn-prem

Web & CMS Plugins / cms-core

Exploitability

No known exploits, KEV entries, or remediation guidance available for this vulnerability yet.

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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

2 techniques

Execution

Initial Access

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References

https://github.com/silverstripe/silverstripe-userforms/security/advisories/GHSA-g8wr-r2v2-vqc6

github.com

https://github.com/silverstripe/silverstripe-userforms/pull/1441

github.com

https://github.com/silverstripe/silverstripe-userforms/pull/1442

github.com

and 5 more references View all →

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