CVE-2026-57736 in HubSpot Plugin
Summary
by MITRE • 07/01/2026
Insertion of Sensitive Information Into Sent Data vulnerability in HubSpot allows Retrieve Embedded Sensitive Data.
This issue affects HubSpot: from n/a through 11.3.51.
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Analysis
by VulDB Data Team • 07/01/2026
The Insertion of Sensitive Information Into Sent Data vulnerability represents a critical security flaw that enables unauthorized retrieval of embedded sensitive data through HubSpot's communication channels. This vulnerability falls under the broader category of information exposure issues and can be classified as CWE-201, which specifically addresses the insertion of sensitive information into data sent to an external party. The flaw manifests when HubSpot applications inadvertently transmit confidential data through various communication protocols including email templates, API responses, or webhook notifications without proper sanitization or access controls.
The technical implementation of this vulnerability stems from insufficient input validation and output encoding mechanisms within HubSpot's data handling processes. When users create marketing campaigns, automated workflows, or custom integrations, the system may include sensitive information such as user credentials, personal identification numbers, internal identifiers, or business-critical data within transmitted messages. The vulnerability affects all versions of HubSpot from the initial release through version 11.3.51, indicating a prolonged period during which this security gap remained unaddressed. Attackers can exploit this weakness by crafting specific requests or manipulating existing workflows to extract embedded sensitive information from system communications.
The operational impact of this vulnerability extends beyond simple data exposure, creating potential pathways for credential theft, identity fraud, and corporate espionage. Organizations utilizing HubSpot for customer relationship management, marketing automation, or sales tracking face significant risks when sensitive data becomes accessible through improperly sanitized communication channels. The vulnerability can be leveraged by both external attackers and privileged insiders to access confidential information that should remain protected within the system's boundaries. This exposure directly violates fundamental security principles of data confidentiality and can result in compliance violations under regulations such as gdpr, hipaa, or pci dss standards.
Security practitioners should consider this vulnerability in relation to ATT&CK technique T1567 which covers "Exfiltration Over Web Service' and T1071.004 which addresses 'Application Layer Protocol: DNS'. The remediation approach requires implementing comprehensive input validation controls, output encoding mechanisms, and strict access control policies within HubSpot's platform architecture. Organizations must ensure that all data transmission channels undergo proper sanitization processes before any sensitive information is included in outbound communications. Additionally, regular security assessments should validate that no embedded sensitive data remains in system outputs, particularly in automated workflows and integration points. The vulnerability highlights the importance of maintaining robust security practices throughout the software development lifecycle, emphasizing the need for continuous monitoring and proactive vulnerability management to prevent similar issues from emerging in future releases.
This specific vulnerability demonstrates how seemingly routine data handling processes can create significant security risks when proper safeguards are not implemented. The affected version range indicates that organizations must prioritize immediate patching and remediation efforts while also implementing additional monitoring measures to detect potential exploitation attempts. Security teams should establish automated scanning procedures to identify any remaining instances of sensitive data leakage within HubSpot systems and maintain vigilance against sophisticated attack patterns that may attempt to leverage this vulnerability for extended periods of unauthorized access.