CyberRota Analysis
AI-GeneratedThe AUSF component of free5GC versions 1.4.4 and earlier is vulnerable due to improper handling of per-subscriber authentication states, allowing an attacker to exploit the N12 interface and flood authentication requests for the same subscriber identifier (SUPI). This results in denial of service for legitimate authentication attempts, as the authentication context is repeatedly overwritten. Organizations utilizing free5GC in their 5G core network should prioritize addressing this vulnerability to prevent potential service disruptions.
Public Exploit Signal
A public exploit, PoC, GitHub repository or Metasploit reference was detected for this CVE.
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Original NVD Description
free5GC is an open-source implementation of the 5G core network. In version 1.4.4 and earlier, the AUSF component stores per-subscriber authentication state in a global sync.Map named AUSFContext.UePool in internal/context/context.go, keyed only by SUPI. Every request handled by internal/sbi/processor/ue_authentication.go creates an AusfUeContext, and AddAusfUeContextToPool executes ausfContext.UePool.Store(ausfUeContext.Supi, ausfUeContext), unconditionally replacing the active context for that SUPI. An attacker with access to the AUSF SBI/N12 interface can send concurrent POST /nausf-auth/v1/ue-authentications requests for the same target SUPI, causing all attempts to share one logical authentication context URL while K_aut, XRES, and EapID are repeatedly overwritten. A valid EAP-AKA' response for an earlier challenge is then checked against the latest context, causing AT_MAC verification to fail and denying authentication to the selected subscriber while the request flood continues. No fixed version is available as of this review.