CVE-2026-43100: Software Security Vulnerability Vulnerability

MODERATE
Advisory Identifier: GHSA-r5qw-5m8q-6774
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CVSS 5.5
CWE-476
Published
Advisory Summary

CVE-2026-43100 is a MODERATE (CVSS 5.5) security vulnerability vulnerability (CWE-476: NULL Pointer Dereference) affecting Software libraries in the Maven ecosystem. The weakness occurs when the product dereferences a pointer that it expects to be valid but is null.. Remediation is available in the latest vendor maintenance releases.

CVE-2026-43100 at a Glance

CVE Identifier CVE-2026-43100
GHSA Identifier GHSA-r5qw-5m8q-6774
Severity MODERATE
CVSS v3.1 Base Score 5.5
CWE Classification CWE-476: NULL Pointer Dereference
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-2026-43100

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-2026-43100, 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 CWE-476: NULL Pointer Dereference, where the product dereferences a pointer that it expects to be valid but is null. 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: bridge: guard local VLAN-0 FDB helpers against NULL vlan group When CONFIG_BRIDGE_VLAN_FILTERING is not set, br_vlan_group() and nbp_vlan_group() return NULL (br_private.h stub definitions). The BR_BOOLOPT_FDB_LOCAL_VLAN_0 toggle code is compiled unconditionally and reaches br_fdb_delete_locals_per_vlan_port() and br_fdb_insert_locals_per_vlan_port(), where the NULL vlan group pointer is dereferenced via list_for_each_entry(v, &vg->vlan_list, vlist). The observed crash is in the delete path, triggered when creating a bridge with IFLA_BR_MULTI_BOOLOPT containing BR_BOOLOPT_FDB_LOCAL_VLAN_0 via RTM_NEWLINK. The insert helper has the same bug pattern. Oops: general protection fault, probably for non-canonical address 0xdffffc0000000056: 0000 [#1] KASAN NOPTI KASAN: null-ptr-deref in range [0x00000000000002b0-0x00000000000002b7] RIP: 0010:br_fdb_delete_locals_per_vlan+0x2b9/0x310 Call Trace: br_fdb_toggle_local_vlan_0+0x452/0x4c0 br_toggle_fdb_local_vlan_0+0x31/0x80 net/bridge/br.c:276 br_boolopt_toggle net/bridge/br.c:313 br_boolopt_multi_toggle net/bridge/br.c:364 br_changelink net/bridge/br_netlink.c:1542 br_dev_newlink net/bridge/br_netlink.c:1575 Add NULL checks for the vlan group pointer in both helpers, returning early when there are no VLANs to iterate. This matches the existing pattern used by other bridge FDB functions such as br_fdb_add() and br_fdb_delete().

References

NVD — CVE-2026-43100 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-43100
git.kernel.org/stable/c/1979645e18... WEB
https://git.kernel.org/stable/c/1979645e1842cb7017525a61a0e0e0beb924d02a
git.kernel.org/stable/c/ddf0ec2d60... WEB
https://git.kernel.org/stable/c/ddf0ec2d600e7dad62b89692749534d7900a732a
git.kernel.org/stable/c/fb612d436f... WEB
https://git.kernel.org/stable/c/fb612d436ff0317659e45a91c25fd7d9516f5b1b

Frequently Asked Questions

What is CVE-2026-43100?
CVE-2026-43100 is a security vulnerability in Software classified as a security vulnerability vulnerability under CWE-476: NULL Pointer Dereference.
Which Software versions are affected?
Affected versions include releases prior to current release patches.
What version fixes CVE-2026-43100?
Upgrading to current release patches (or the latest patched release for your respective branch) resolves the vulnerability.
What is the CVSS score of CVE-2026-43100?
CVE-2026-43100 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-2026-43100?
CVE-2026-43100 is classified under CWE-476: NULL Pointer Dereference (The product dereferences a pointer that it expects to be valid but is NULL.).
How can I check Maven dependencies for CVE-2026-43100?
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-r5qw-5m8q-6774",
  "modified" : "2026-05-11T18:31:35Z",
  "published" : "2026-05-06T12:30:27Z",
  "aliases" : [ "CVE-2026-43100" ],
  "details" : "In the Linux kernel, the following vulnerability has been resolved:\n\nbridge: guard local VLAN-0 FDB helpers against NULL vlan group\n\nWhen CONFIG_BRIDGE_VLAN_FILTERING is not set, br_vlan_group() and\nnbp_vlan_group() return NULL (br_private.h stub definitions). The\nBR_BOOLOPT_FDB_LOCAL_VLAN_0 toggle code is compiled unconditionally and\nreaches br_fdb_delete_locals_per_vlan_port() and\nbr_fdb_insert_locals_per_vlan_port(), where the NULL vlan group pointer\nis dereferenced via list_for_each_entry(v, &vg->vlan_list, vlist).\n\nThe observed crash is in the delete path, triggered when creating a\nbridge with IFLA_BR_MULTI_BOOLOPT containing BR_BOOLOPT_FDB_LOCAL_VLAN_0\nvia RTM_NEWLINK. The insert helper has the same bug pattern.\n\n  Oops: general protection fault, probably for non-canonical address 0xdffffc0000000056: 0000 [#1] KASAN NOPTI\n  KASAN: null-ptr-deref in range [0x00000000000002b0-0x00000000000002b7]\n  RIP: 0010:br_fdb_delete_locals_per_vlan+0x2b9/0x310\n  Call Trace:\n   br_fdb_toggle_local_vlan_0+0x452/0x4c0\n   br_toggle_fdb_local_vlan_0+0x31/0x80 net/bridge/br.c:276\n   br_boolopt_toggle net/bridge/br.c:313\n   br_boolopt_multi_toggle net/bridge/br.c:364\n   br_changelink net/bridge/br_netlink.c:1542\n   br_dev_newlink net/bridge/br_netlink.c:1575\n\nAdd NULL checks for the vlan group pointer in both helpers, returning\nearly when there are no VLANs to iterate. This matches the existing\npattern used by other bridge FDB functions such as br_fdb_add() and\nbr_fdb_delete().",
  "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-2026-43100"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/1979645e1842cb7017525a61a0e0e0beb924d02a"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/ddf0ec2d600e7dad62b89692749534d7900a732a"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/fb612d436ff0317659e45a91c25fd7d9516f5b1b"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-476" ],
    "severity" : "MODERATE",
    "github_reviewed" : false,
    "github_reviewed_at" : null,
    "nvd_published_at" : "2026-05-06T10:16:23Z"
  }
}