CVE-2026-0767 in Open WebUI
Summary
by MITRE • 01/23/2026
Open WebUI Cleartext Transmission of Credentials Information Disclosure Vulnerability. This vulnerability allows network-adjacent attackers to disclose sensitive information on affected installations of Open WebUI. Authentication is not required to exploit this vulnerability.
The specific flaw exists within the handling of credentials provided to the endpoint. The issue results from transmitting sensitive information in plaintext. An attacker can leverage this vulnerability to disclose transmitted credentials, leading to further compromise. Was ZDI-CAN-28259.
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Analysis
by VulDB Data Team • 01/31/2026
The CVE-2026-0767 vulnerability represents a critical security flaw in Open WebUI that exposes credentials through cleartext transmission mechanisms. This vulnerability falls under the category of information disclosure issues and specifically targets the authentication and credential handling processes within the web interface. The flaw exists in how the system processes and transmits user credentials, creating an attack surface that can be exploited by adversaries positioned within the network adjacent to the affected system. The vulnerability is particularly concerning because it requires no authentication to exploit, meaning that any network-adjacent attacker can potentially intercept and decode transmitted credentials without prior access to the system. This type of vulnerability directly violates security best practices and represents a fundamental failure in secure communication protocols.
The technical implementation of this vulnerability stems from the application's failure to employ encrypted communication channels for credential transmission. When users provide authentication information to the Open WebUI system, the credentials are sent in plaintext format over the network, making them susceptible to interception through various network monitoring and packet capture techniques. The flaw is categorized as a CWE-312 (Cleartext Storage of Sensitive Information) and CWE-319 (Cleartext Transmission of Sensitive Information) according to the Common Weakness Enumeration standards. This means that sensitive data is being transmitted without proper encryption, allowing attackers to capture and decode credentials using standard network analysis tools. The vulnerability affects the core authentication mechanism and represents a failure in implementing secure communication protocols such as TLS/SSL for protecting sensitive information in transit.
The operational impact of this vulnerability extends beyond simple credential theft, creating a pathway for further system compromise and lateral movement within network environments. Once an attacker successfully intercepts transmitted credentials, they can potentially gain unauthorized access to user accounts, administrative interfaces, and other sensitive system resources. This vulnerability directly maps to ATT&CK technique T1078 (Valid Accounts) and T1566 (Phishing) as it enables unauthorized access through credential compromise. The implications are particularly severe for organizations that rely on Open WebUI for critical operations, as the stolen credentials could provide access to sensitive data repositories, system configurations, and other privileged resources. The vulnerability also creates opportunities for attackers to establish persistent access through compromised accounts and can lead to cascading security failures throughout the affected network infrastructure.
Organizations should implement immediate mitigations to address this vulnerability by enforcing mandatory encryption for all credential transmissions and ensuring that TLS/SSL protocols are properly configured and enforced. The recommended approach includes implementing transport layer security measures such as HTTPS with strong encryption algorithms, disabling cleartext protocols, and ensuring that all credential handling processes utilize encrypted communication channels. System administrators should also consider implementing network segmentation and monitoring to detect unauthorized credential interception attempts. Additionally, organizations should conduct comprehensive security assessments to identify any other applications or services that might be using similar cleartext transmission patterns, as this vulnerability represents a broader pattern of insecure communication practices. The remediation process should also include user education about the importance of secure credential handling and the risks associated with plaintext transmission of sensitive information.