The vulnerability is in the sgwc_s5c_handle_modify_bearer_response routine of Open5GS’s SGWC component. A malformed Modify Bearer Response message enables a remote attacker to trigger a logic path that fails to properly release resources, resulting in a denial of service. The attacker need not obtain privileged credentials; the exploit operates over the network interface used for S5C signalling and is publicly available.

Products affected are Open5GS deployments using the SGWC module, specifically versions up to and including 2.7.6. The vulnerability pertains to the open-source SGWC component of Open5GS.

The CVSS score of 6.9 indicates a moderate severity. The EPSS value of less than one percent suggests a low likelihood of widespread exploitation, and the vulnerability is not tracked in the CISA KEV catalog. Nevertheless, the remote attack vector and availability impact mean that a service outage could be disruptive to subscriber connectivity. The fix is publicly available as commit b19cf6a.