A vulnerability was discovered in Open5GS up to version 2.7.7 in the function ogs_pcc_rule_install_flow_from_media within the library /lib/proto/types.c. Manipulating the input to this function can cause the process to hang, leading to a denial of service. The exploit is remote, requires only the ability to invoke the vulnerable function, and a public exploit is already available, making it reachable to attackers.

The affected product is Open5GS, a free and open‑source 5G core network implementation. Any installation of Open5GS that includes a component executing the ogs_pcc_rule_install_flow_from_media function and that runs up to and including version 2.7.7 is vulnerable. Users should verify the version they are running and upgrade if it falls within this range.

The CVSS score of 6.9 indicates medium severity. While the EPSS score is not available, the fact that the exploit has been publicly released and can be launched remotely suggests a notable risk for systems that expose Open5GS to untrusted networks. The vulnerability is not yet listed in CISA KEV, but the lack of an official fix in the project increases the exposure window.