CVE-2021-47452: Software Security Vulnerability Vulnerability

MODERATE
Advisory Identifier: GHSA-hxw5-pvw5-67pp
Share
CVSS 5.5
Published
Advisory Summary

CVE-2021-47452 is a MODERATE (CVSS 5.5) security vulnerability vulnerability (General Security Weakness) affecting Software libraries in the Maven ecosystem. Remediation is available in the latest vendor maintenance releases.

CVE-2021-47452 at a Glance

CVE Identifier CVE-2021-47452
GHSA Identifier GHSA-hxw5-pvw5-67pp
Severity MODERATE
CVSS v3.1 Base Score 5.5
CWE Classification General Security Weakness
Affected Product Software
Package Ecosystem Maven
Published Date
Last Updated

Security Impact

CVSS: 5.5

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

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

How to Fix CVE-2021-47452

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

Verify Direct and Transitive Dependencies

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

mvn dependency:tree

How to Check if You Are Affected

To determine whether your Java application is affected by CVE-2021-47452, inspect your build dependencies using the Maven Dependency Plugin:

mvn dependency:tree

Analyze the terminal output to locate any version of Software in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than the patched release), your application is affected.

Note: The mvn dependency:tree command inspects the resolved dependency graph declared in your project's POM files; it does not perform automated security scanning or inspect runtime dynamic classpaths. Always verify runtime container classpaths and shaded JARs.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under General Security Weakness. In Software, 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

In the Linux kernel, the following vulnerability has been resolved: netfilter: nf_tables: skip netdev events generated on netns removal syzbot reported following (harmless) WARN: WARNING: CPU: 1 PID: 2648 at net/netfilter/core.c:468 nft_netdev_unregister_hooks net/netfilter/nf_tables_api.c:230 [inline] nf_tables_unregister_hook include/net/netfilter/nf_tables.h:1090 [inline] __nft_release_basechain+0x138/0x640 net/netfilter/nf_tables_api.c:9524 nft_netdev_event net/netfilter/nft_chain_filter.c:351 [inline] nf_tables_netdev_event+0x521/0x8a0 net/netfilter/nft_chain_filter.c:382 reproducer: unshare -n bash -c 'ip link add br0 type bridge; nft add table netdev t ; \ nft add chain netdev t ingress \{ type filter hook ingress device "br0" \ priority 0\; policy drop\; \}' Problem is that when netns device exit hooks create the UNREGISTER event, the .pre_exit hook for nf_tables core has already removed the base hook. Notifier attempts to do this again. The need to do base hook unregister unconditionally was needed in the past, because notifier was last stage where reg->dev dereference was safe. Now that nf_tables does the hook removal in .pre_exit, this isn't needed anymore.

References

NVD — CVE-2021-47452 NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-47452
git.kernel.org/stable/c/68a3765c65... WEB
https://git.kernel.org/stable/c/68a3765c659f809dcaac20030853a054646eb739
git.kernel.org/stable/c/90c7c58aa2... WEB
https://git.kernel.org/stable/c/90c7c58aa2bd02c65a4c63b7dfe0b16eab12cf9f

Frequently Asked Questions

What is CVE-2021-47452?
CVE-2021-47452 is a security vulnerability in Software classified as a security vulnerability vulnerability under General Security Weakness.
Which Software versions are affected?
Affected versions include releases prior to current release patches.
What version fixes CVE-2021-47452?
Upgrading to current release patches (or the latest patched release for your respective branch) resolves the vulnerability.
What is the CVSS score of CVE-2021-47452?
CVE-2021-47452 has a CVSS v3.1 base score of 5.5 (MODERATE) with vector string CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H.
What CWE is associated with CVE-2021-47452?
CVE-2021-47452 is classified under General Security Weakness.
How can I check Maven dependencies for CVE-2021-47452?
Run the dependency tree command: 'mvn dependency:tree'. 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-hxw5-pvw5-67pp",
  "modified" : "2025-09-29T18:33:07Z",
  "published" : "2024-05-22T09:31:45Z",
  "aliases" : [ "CVE-2021-47452" ],
  "details" : "In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: nf_tables: skip netdev events generated on netns removal\n\nsyzbot reported following (harmless) WARN:\n\n WARNING: CPU: 1 PID: 2648 at net/netfilter/core.c:468\n  nft_netdev_unregister_hooks net/netfilter/nf_tables_api.c:230 [inline]\n  nf_tables_unregister_hook include/net/netfilter/nf_tables.h:1090 [inline]\n  __nft_release_basechain+0x138/0x640 net/netfilter/nf_tables_api.c:9524\n  nft_netdev_event net/netfilter/nft_chain_filter.c:351 [inline]\n  nf_tables_netdev_event+0x521/0x8a0 net/netfilter/nft_chain_filter.c:382\n\nreproducer:\nunshare -n bash -c 'ip link add br0 type bridge; nft add table netdev t ; \\\n nft add chain netdev t ingress \\{ type filter hook ingress device \"br0\" \\\n priority 0\\; policy drop\\; \\}'\n\nProblem is that when netns device exit hooks create the UNREGISTER\nevent, the .pre_exit hook for nf_tables core has already removed the\nbase hook.  Notifier attempts to do this again.\n\nThe need to do base hook unregister unconditionally was needed in the past,\nbecause notifier was last stage where reg->dev dereference was safe.\n\nNow that nf_tables does the hook removal in .pre_exit, this isn't\nneeded anymore.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"
  } ],
  "affected" : [ ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2021-47452"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/68a3765c659f809dcaac20030853a054646eb739"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/90c7c58aa2bd02c65a4c63b7dfe0b16eab12cf9f"
  } ],
  "database_specific" : {
    "cwe_ids" : [ ],
    "severity" : "MODERATE",
    "github_reviewed" : false,
    "github_reviewed_at" : null,
    "nvd_published_at" : "2024-05-22T07:15:10Z"
  }
}