A vulnerability in the yuarel_parse function within Open5GS's NRF component allows an attacker to craft malicious hnrf-uri arguments and trigger a denial of service in the NRF's SBI interface. The flaw, identified as CWE-404, arises from improper validation of the URI string, causing the process to crash when malformed data is received. Executing the exploit can liberate the NRF service to become unavailable, potentially disrupting network services for a user or operator while the affected system is still in the attacker's control.

The issue affects Open5GS deployments up to version 2.7.7. Any installation using the NRF component on these releases is susceptible. The vulnerability resides in the /lib/sbi/conv.c library and can be triggered remotely by sending requests to the NRF's SBI endpoint with a crafted hnrf-uri parameter. No downstream products beyond Open5GS were identified at this time.

The CVSS score is 5.3, indicating a moderate impact. EPSS is currently unavailable, and the vulnerability is not listed in the CISA KEV catalog, suggesting it has not yet been broadly exploited. Nevertheless, the attack vector is remote and the mitigation requires timely patching or mitigations. An attacker who can reach the NRF's SBI interface could repeatedly provoke service crashes, leading to disrupted network connectivity for connected devices.