This vulnerability in Open5GS (up to version 2.7.7) involves improper handling of the 'pei' argument in the function udr_nudr_dr_handle_subscription_context within the UDR component. An attacker can remotely manipulate this argument to trigger a denial of service condition. The vulnerability requires no user interaction and can be exploited with low attack complexity and low privileges. The CVSS 4.0 base score is 5.3, indicating medium severity. The Open5GS project has been informed but has not issued a fix or official remediation guidance.

Successful exploitation results in denial of service of the affected Open5GS UDR component, potentially disrupting network functions relying on this service. The attack can be launched remotely and does not require user interaction or high privileges, increasing the risk of disruption. There is no evidence of exploitation in the wild at this time.

Patch status is not yet confirmed — check the Open5GS project advisory or repository for updates. Since no official fix or remediation guidance has been provided, users should monitor the project for forthcoming patches. In the meantime, consider limiting network exposure of the UDR component to trusted sources to reduce attack surface.