CVE-2026-4531: Github.com/free5gc/amf Denial of Service Vulnerability

MODERATE
Advisory Identifier: GHSA-xq44-64rg-8g3h
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CVSS 5.3
CWE-404
Published
Advisory Summary

CVE-2026-4531 is a MODERATE (CVSS 5.3) denial of service vulnerability (CWE-404: Improper Resource Shutdown or Release) affecting Github.com/free5gc/amf libraries in the Go ecosystem. The issue involves free5gc amf is vulnerable to dos through its handleregistrationcomplete function. Remediation is available by upgrading affected packages to version 1.4.3-0.20260306074636-52e9386401ce.

CVE-2026-4531 at a Glance

CVE Identifier CVE-2026-4531
GHSA Identifier GHSA-xq44-64rg-8g3h
Severity MODERATE
CVSS v3.1 Base Score 5.3
CWE Classification CWE-404: Improper Resource Shutdown or Release
Affected Product Github.com/free5gc/amf
Package Ecosystem Go
Published Date
Last Updated

Security Impact

CVSS: 5.3

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L).

Attack Vector Network (AV:N)
Attack Complexity Low (AC:L)
Privileges Required None (PR:N)
User Interaction None (UI:N)
Scope Unchanged (S:U)
Confidentiality None (C:N)
Integrity None (I:N)
Availability Low (A:L)

How to Fix CVE-2026-4531

To remediate this vulnerability, upgrade all affected Github.com/free5gc/amf dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

github.com/free5gc/amf fixed: 1.4.3-0.20260306074636-52e9386401ce 
Upgrade github.com/free5gc/amf to 1.4.3-0.20260306074636-52e9386401ce
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

inspect dependencies for github.com/free5gc/amf

How to Check if You Are Affected

To determine whether your application is affected by CVE-2026-4531, inspect your project dependencies for Github.com/free5gc/amf:

inspect dependencies for github.com/free5gc/amf

Analyze the terminal output to locate any version of Github.com/free5gc/amf in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 1.4.3-0.20260306074636-52e9386401ce), your application is affected.

Note: Verify declared build manifests and deployed runtime container environments.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-404: Improper Resource Shutdown or Release, where the product does not release or incorrectly releases a resource before it is made available for re-use. In Github.com/free5gc/amf, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

A weakness has been identified in Free5GC 4.1.0. Affected is the function HandleRegistrationComplete of the file internal/gmm/handler.go of the component AMF. Executing a manipulation can lead to denial of service. The attack may be performed from remote. This patch is called 52e9386401ce56ea773c5aa587d4cdf7d53da799. It is best practice to apply a patch to resolve this issue.

CVE-2026-4531 Affected Github.com/free5gc/amf Versions

1 component(s)
Fixed Versions:
1.4.3-0.20260306074636-52e9386401ce
Product / Package Ecosystem Affected Versions Fixed Version
github.com/free5gc/amf
golang/github.com/free5gc/amf
Go
< 1.4.3-0.20260306074636-52e9386401ce
1.4.3-0.20260306074636-52e9386401ce

References

NVD — CVE-2026-4531 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-4531
Github.com/free5gc/amf Source Repository REPOSITORY
https://github.com/free5gc/free5gc/issues/792
Github.com/free5gc/amf Source Repository REPOSITORY
https://github.com/free5gc/amf/pull/198
Security Fix Commit FIX COMMIT
https://github.com/free5gc/amf/commit/52e9386401ce56ea773c5aa587d4cdf7d53da799
Github.com/free5gc/amf Source Repository REPOSITORY
https://github.com/free5gc/amf
vuldb.com/ WEB
https://vuldb.com/?ctiid.352319
vuldb.com/ WEB
https://vuldb.com/?id.352319
vuldb.com/ WEB
https://vuldb.com/?submit.774073

Frequently Asked Questions

What is CVE-2026-4531?
CVE-2026-4531 is a security vulnerability in Github.com/free5gc/amf involving Free5GC AMF is vulnerable to DoS through its HandleRegistrationComplete function under CWE-404: Improper Resource Shutdown or Release.
Which Github.com/free5gc/amf versions are affected?
Affected versions include releases prior to 1.4.3-0.20260306074636-52e9386401ce across affected packages: github.com/free5gc/amf.
What version fixes CVE-2026-4531?
Upgrading to 1.4.3-0.20260306074636-52e9386401ce (or the latest patched release for your respective branch) resolves the vulnerability.
Is github.com/free5gc/amf affected?
Yes, github.com/free5gc/amf is affected in releases prior to 1.4.3-0.20260306074636-52e9386401ce. Upgrade your dependency to 1.4.3-0.20260306074636-52e9386401ce or later.
What is the CVSS score of CVE-2026-4531?
CVE-2026-4531 has a CVSS v3.1 base score of 5.3 (MODERATE) with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L.
What CWE is associated with CVE-2026-4531?
CVE-2026-4531 is classified under CWE-404: Improper Resource Shutdown or Release (The product does not release or incorrectly releases a resource before it is made available for re-use.).
How can I check Go dependencies for CVE-2026-4531?
Run the dependency tree command: 'inspect dependencies for github.com/free5gc/amf'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-xq44-64rg-8g3h",
  "modified" : "2026-03-24T20:15:31Z",
  "published" : "2026-03-22T03:30:25Z",
  "aliases" : [ "CVE-2026-4531" ],
  "summary" : "Free5GC AMF is vulnerable to DoS through its HandleRegistrationComplete function",
  "details" : "A weakness has been identified in Free5GC 4.1.0. Affected is the function HandleRegistrationComplete of the file internal/gmm/handler.go of the component AMF. Executing a manipulation can lead to denial of service. The attack may be performed from remote. This patch is called 52e9386401ce56ea773c5aa587d4cdf7d53da799. It is best practice to apply a patch to resolve this issue.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L"
  }, {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Go",
      "name" : "github.com/free5gc/amf"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "1.4.3-0.20260306074636-52e9386401ce"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-4531"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/free5gc/free5gc/issues/792"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/free5gc/amf/pull/198"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/free5gc/amf/commit/52e9386401ce56ea773c5aa587d4cdf7d53da799"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/free5gc/amf"
  }, {
    "type" : "WEB",
    "url" : "https://vuldb.com/?ctiid.352319"
  }, {
    "type" : "WEB",
    "url" : "https://vuldb.com/?id.352319"
  }, {
    "type" : "WEB",
    "url" : "https://vuldb.com/?submit.774073"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-404" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-03-24T20:15:30Z",
    "nvd_published_at" : "2026-03-22T02:15:59Z"
  }
}