Vulnerability in github.com/free5gc/nef (CVE-2026-44327)
Summary
Vulnerability in github.com/free5gc/nef (CVE-2026-44327). Data can be tampered with by attackers. Exploitable via Authorization.
Original description
The description as published by the source.
free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's NEF mounts the nnef-oam route group without inbound OAuth2/bearer-token authorization. A network attacker who can reach NEF on the SBI can hit the OAM route with no Authorization header at all and the handler returns 200 OK. The current OAM handler is a stub that returns null, but the structural defect is route-group-scoped: the entire OAM route group has no inbound auth middleware, so every future OAM operation added to this group inherits the missing auth boundary by default. This vulnerability is fixed in 4.2.2.
Source: GitHub Security Advisories (Global) NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-44327 has been found in github.com/free5gc/nef.
Attackers can target a specific entry point like Authorization over the network to misuse the product.
Data can be tampered with by attackers. CVSS score: 10.0/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "github.com/free5gc/nef CVE-2026-44327" on the vendor's site.
CVE-2026-44327 (github.com/free5gc/nef) — CWE-306 / CVSS v3 10.0
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Attack surface: Authorization / null / GET / GetTokenCtx
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (CWE-306) exists in github.com/free5gc/nef. Attackers reach the vulnerable code path via Authorization without authentication.
Check the vendor advisory for the affected versions of github.com/free5gc/nef. Attack surface: Authorization / null / GET / GetTokenCtx.
Severity: Critical (CVSS 10.0/10). Data can be tampered with by attackers.
Update to the patched release per vendor advisory.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'github.com/free5gc/nef' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
grep -r 'github.com/free5gc/nef' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
github.com/free5gc/nefを grep し、稼働しているサービス・バージョンを把握する。 -
2Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Affected packages
References
- advisory github.com
- advisory nvd.nist.gov
- advisory github.com
- package github.com
- patch github.com
- report github.com
- web github.com