CVE-2026-41136
CVE-2026-41136 is a remote code execution vulnerability in github.com/free5gc/amf. O3 Security confirms whether CVE-2026-41136 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
free5GC AMF missing default case in Content-Type switch in HTTPUEContextTransfer
Real-World Exposure
github.com/free5gc/amfReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.
Description
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.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/free5gc/amf | all versions | No fix |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/free5gc/amf. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Remediation status
No patched version of github.com/free5gc/amf has shipped for CVE-2026-41136 yet. Where your build allows, override or pin the dependency away from the vulnerable range, and apply any maintainer-recommended mitigation.
Mitigate without a patch
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2026-41136 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2026-41136. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-41136 in your dependencies?
O3 detects CVE-2026-41136 across Go dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.