CVE-2026-27643: medium-severity vulnerability in free5gc udr
free5GC has improper error handling in NEF with information exposure
Published · Updated
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13Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 6.6epss 0.3%
free5GC UDR is the user data repository (UDR) for free5GC, an an open-source project for 5th generation (5G) mobile core networks. In versions up to and including 1.4.1, the NEF component reliably leaks internal parsing error details (e.g., invalid character 'n' after top-level value) to remote clients, which can aid attackers in service fingerprinting. All deployments of free5GC using the Nnef_PfdManagement service may be affected. free5gc/udr pull request 56 contains a patch for the issue. There is no direct workaround at the application level. The recommendation is to apply the provided patch.
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:U
Affected products
free5gc · udrRelated CVEs — free5gc udr
In the same product, most dangerous first.
CVE-2026-40343MEDIUMfree5GC UDR: Fail-open handling in PolicyDataSubsToNotifyPost allows unintended subscription creationEPSS 8.6%CVE-2025-69253MEDIUMfree5GC vulnerable to improper error handling in NEF with information exposureEPSS 0.4%CVE-2025-69208LOWfree5GC UDR's NEF incorrectly returns 500 for missing PFD data (UDR 404) in Nnef_PfdManagement GET requestEPSS 0.3%