A newly disclosed vulnerability in F5OS, tracked as CVE-2025-46265, allows authenticated remote users to gain elevated privileges through improper authorization checks. The flaw affects systems using LDAP, RADIUS, or TACACS+ for authentication and has been assigned a CVSS 4.0 score of 8.7 (HIGH). This vulnerability poses a significant risk to organizations using F5OS for network infrastructure management.
Technical Overview of CVE-2025-46265
The vulnerability stems from incorrect authorization checks (CWE-863) in F5OS, where authenticated users may be assigned higher privilege roles than intended. According to F5’s advisory (K000139503), the issue specifically impacts remote authentication methods including LDAP, RADIUS, and TACACS+. The vulnerability is network-exploitable with low attack complexity and requires no user interaction, potentially leading to complete compromise of confidentiality and integrity.
F5 has confirmed that end-of-technical-support (EoTS) versions are not evaluated for this vulnerability. While the exact affected versions haven’t been publicly disclosed, organizations running supported versions should immediately check for available patches. The NVD entry notes that successful exploitation could allow attackers to gain administrative control over affected F5OS systems.
Impact and Affected Systems
The vulnerability primarily affects enterprise environments using F5OS with external authentication services. Organizations that have integrated their F5 infrastructure with directory services are particularly at risk. The potential impacts include unauthorized configuration changes, policy modifications, and complete system compromise.
Security teams should note that this vulnerability differs from other recent F5OS issues such as CVE-2025-36546 (command injection) and CVE-2025-43878 (memory leaks). While those vulnerabilities primarily affected Appliance Mode, CVE-2025-46265 specifically targets the authorization subsystem for remote authenticated users.
Mitigation and Remediation
F5 has released patches for supported versions, which should be applied immediately. For organizations unable to patch immediately, the following temporary mitigation strategies are recommended:
- Restrict LDAP/RADIUS/TACACS+ access to F5OS management interfaces
- Implement network segmentation to limit access to F5OS administrative interfaces
- Monitor authentication logs for unusual privilege escalations
- Audit LDAP group memberships and RADIUS/TACACS+ authorization rules
System administrators should also review SSH key configurations in Appliance Mode, as credential leaks could compound the risk from this vulnerability. Continuous monitoring for suspicious authentication attempts is advised, particularly for accounts that suddenly gain elevated privileges.
Security Implications and Best Practices
This vulnerability highlights the importance of proper authorization controls in network infrastructure devices. Organizations should implement the principle of least privilege for all authentication methods and regularly audit role assignments. The case also demonstrates why end-of-life systems pose significant security risks, as they receive no vulnerability evaluations or patches.
For comprehensive protection, security teams should combine patching with network monitoring for anomalous authentication patterns. SIEM rules should be updated to detect privilege escalation attempts, and all authentication logs should be centrally collected and analyzed. Regular reviews of access control configurations can help prevent similar issues from being exploited in the future.
Conclusion
CVE-2025-46265 represents a serious threat to organizations using F5OS with external authentication services. The high CVSS score reflects the potential impact of successful exploitation. While patches are available, proper configuration management and monitoring remain essential for comprehensive protection. Security teams should prioritize addressing this vulnerability while also reviewing related authentication and authorization controls across their infrastructure.
References
- “CVE-2025-46265 Detail,” National Vulnerability Database, [Online]. Available: https://nvd.nist.gov/vuln/detail/CVE-2025-46265 [Accessed: May 8, 2025].
- “K000139503: F5OS vulnerability CVE-2025-46265,” F5 Support, [Online]. Available: https://my.f5.com/manage/s/article/K000139503 [Accessed: May 8, 2025].
- “GHSA-5r29-8gxx-9wp7: Next.js authorization bypass,” GitHub Advisory Database, [Online]. Available: https://github.com/advisories/GHSA-5r29-8gxx-9wp7 [Accessed: May 8, 2025].
- “CVE-2025-29927: Next.js authorization bypass technical analysis,” JFrog Security Research, [Online]. Available: https://jfrog.com/blog/cve-2025-29927-next-js-authorization-bypass [Accessed: May 8, 2025].
- “Emerging threat: Next.js CVE-2025-29927,” CyCognito Threat Advisory, [Online]. Available: https://cycognito.com/blog/emerging-threat-next-js-cve-2025-29927 [Accessed: May 8, 2025].
