CVE-2026-41136: free5GC AMF: Missing default case in Content-Type switch in HTTPUEContextTransfer

CVE-2026-41136 · Severity: medium · CVSS 5.3 · Published 2026-04-22

free5GC AMF provides Access & Mobility Management Function (AMF) for free5GC, an an open-source project for 5th generation (5G) mobile core networks. Prior to version 1.4.3, the `HTTPUEContextTransfer` handler in `internal/sbi/api_communication.go` does not include a `default` case in the `Content-Type` switch statement. When a request arrives with an unsupported `Content-Type`, the deserialization step is silently skipped, `err` remains `nil`, and the processor is invoked with a completely uninitialized `UeContextTransferRequest` object. Version 1.4.3 contains a fix.

Technologies: free5GC, github.com/free5gc/amf (Go). Vendors: free5GC, Go.

Quick answers

Is CVE-2026-41136 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-41136 being exploited in the wild.
How severe is CVE-2026-41136?
Medium severity, with a CVSS score of 5.3, published 22 April 2026.
Which products and versions are affected?
github.com/free5gc/amf (Go) <= 1.4.3, SEMVER:introduced=0, SEMVER:introduced=0,last_affected=1.4.3.
Is there a fix for CVE-2026-41136?
No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
Am I affected by CVE-2026-41136?
Check whether you run free5GC Amf, free5GC or github.com/free5gc/amf (Go) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Affected products

  • free5GC Amf
  • free5GC
  • github.com/free5gc/amf (Go) <= 1.4.3, SEMVER:introduced=0, SEMVER:introduced=0,last_affected=1.4.3

Identifiers

  • CVE-2026-41136
  • GHSA-r99v-75p9-xqm5
  • GO-2026-5613

References

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