CVE-2021-33605 in Vaadin
Summary
by MITRE • 08/25/2021
Improper check in CheckboxGroup in com.vaadin:vaadin-checkbox-flow versions 1.2.0 prior to 2.0.0 (Vaadin 12.0.0 prior to 14.0.0), 2.0.0 prior to 3.0.0 (Vaadin 14.0.0 prior to 14.5.0), 3.0.0 through 4.0.1 (Vaadin 15.0.0 through 17.0.11), 14.5.0 through 14.6.7 (Vaadin 14.5.0 through 14.6.7), and 18.0.0 through 20.0.5 (Vaadin 18.0.0 through 20.0.5) allows attackers to modify the value of a disabled Checkbox inside enabled CheckboxGroup component via unspecified vectors.
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Analysis
by VulDB Data Team • 08/29/2021
The vulnerability identified as CVE-2021-33605 affects the Vaadin framework's CheckboxGroup component across multiple version ranges, representing a critical security flaw that undermines the intended access control mechanisms within web applications. This issue specifically targets the improper validation of checkbox states within a group structure, creating a scenario where attackers can manipulate disabled checkboxes through unspecified attack vectors. The vulnerability exists in versions prior to 2.0.0 for Vaadin 12, prior to 3.0.0 for Vaadin 14, through version 4.0.1 for Vaadin 15-17, and across various releases in Vaadin 14.5.0 through 14.6.7 as well as Vaadin 18.0.0 through 20.0.5. The flaw manifests when a CheckboxGroup component contains both enabled and disabled checkboxes, where the security controls fail to properly validate user input against the expected state of individual checkboxes within the group.
The technical implementation of this vulnerability stems from inadequate state validation within the CheckboxGroup component's handling of user interactions. When a checkbox within a group is marked as disabled, the system should prevent any modification attempts from external sources, including client-side manipulation or server-side data injection. However, the flawed implementation allows attackers to bypass these state restrictions through unspecified vectors that likely involve manipulation of request parameters or direct DOM manipulation. This represents a classic case of insufficient input validation and access control enforcement, aligning with CWE-284 which addresses improper access control mechanisms. The vulnerability essentially allows privilege escalation within the context of the web application's checkbox handling logic, where a user can effectively override the intended disabled state of individual checkboxes.
The operational impact of this vulnerability extends beyond simple data manipulation to potentially compromise application integrity and user experience. Attackers could exploit this flaw to enable or disable checkboxes that should remain in their intended state, potentially allowing unauthorized access to features or data that should be restricted. This type of vulnerability is particularly concerning in applications where checkbox selections control access to sensitive functionality, user permissions, or data processing workflows. The attack surface is broad given the widespread use of Vaadin framework components across enterprise applications, making this vulnerability particularly dangerous for organizations using affected versions. From an adversarial perspective, this vulnerability maps to ATT&CK technique T1068 which involves exploiting local system permissions and T1546 which covers privilege escalation through modification of system processes.
Organizations using affected Vaadin versions should immediately implement mitigation strategies including immediate patching to versions 2.0.0 or later for Vaadin 12, 3.0.0 or later for Vaadin 14, and appropriate updates for all other affected version ranges. The patching strategy should include comprehensive testing to ensure that the fix does not introduce regressions in existing functionality while maintaining the intended user experience. Additionally, developers should implement additional client-side validation and server-side state verification for checkbox components, particularly in scenarios where checkbox states are dynamically determined or controlled by user roles. Security teams should monitor for potential exploitation attempts through web application firewalls and log analysis, focusing on unusual checkbox state modification patterns that might indicate attempted exploitation of this vulnerability. The remediation process should also include code reviews of existing checkbox group implementations to identify and address similar patterns that might exist in custom code or third-party components.