CVE-2021-43820 : What You Need to Know
Learn about CVE-2021-43820, a high severity vulnerability in Seafile that allows unauthorized access to data. Find out the affected systems, exploitation method, and mitigation steps.
Seafile is an open source cloud storage system with a vulnerability that allows an attacker to bypass permissions checks, potentially leading to unauthorized access to data.
Understanding CVE-2021-43820
Seafile's design flaw enables unauthorized access to data through an authorization bypass.
What is CVE-2021-43820?
Seafile's sync token caching in memory allows the circumvention of library data access restrictions, enabling access to data from any known library.
The Impact of CVE-2021-43820
The vulnerability poses a high severity risk with confidentiality, integrity, and no user interaction required for exploitation.
Technical Details of CVE-2021-43820
Seafile's vulnerability specifics and affected systems.
Vulnerability Description
- An authorization bypass through user-controlled keys (CWE-639) allows unrestricted data access.
Affected Systems and Versions
- Products: seafile-server
- Vendor: Haiwen
- Versions Affected: Community Edition < 8.0.8, Pro Edition < 8.0.15
Exploitation Mechanism
- Attacker needs to discover the ID of a restricted library to exploit the vulnerability.
Mitigation and Prevention
Steps to mitigate and prevent unauthorized data access.
Immediate Steps to Take
- Update Seafile to versions 8.0.8 for Community Edition or 8.0.15 for Pro Edition.
- Monitor for unusual data access patterns.
Long-Term Security Practices
- Regularly review and update access controls.
- Educate users on data security best practices.
Patching and Updates
- Apply vendor-provided patches promptly to fix the vulnerability.