CVE-2021-47266: Software Security Vulnerability Vulnerability

MODERATE
Advisory Identifier: GHSA-8cxw-6695-4jq3
CVSS 5.5
CWE-476
Published
Advisory Summary

CVE-2021-47266 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-2021-47266 at a Glance

CVE Identifier CVE-2021-47266
GHSA Identifier GHSA-8cxw-6695-4jq3
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-2021-47266

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-2021-47266, 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: RDMA/ipoib: Fix warning caused by destroying non-initial netns After the commit 5ce2dced8e95 ("RDMA/ipoib: Set rtnl_link_ops for ipoib interfaces"), if the IPoIB device is moved to non-initial netns, destroying that netns lets the device vanish instead of moving it back to the initial netns, This is happening because default_device_exit() skips the interfaces due to having rtnl_link_ops set. Steps to reporoduce: ip netns add foo ip link set mlx5_ib0 netns foo ip netns delete foo WARNING: CPU: 1 PID: 704 at net/core/dev.c:11435 netdev_exit+0x3f/0x50 Modules linked in: xt_CHECKSUM xt_MASQUERADE xt_conntrack ipt_REJECT nf_reject_ipv4 nft_compat nft_counter nft_chain_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 nf_tables nfnetlink tun d fuse CPU: 1 PID: 704 Comm: kworker/u64:3 Tainted: G S W 5.13.0-rc1+ #1 Hardware name: Dell Inc. PowerEdge R630/02C2CP, BIOS 2.1.5 04/11/2016 Workqueue: netns cleanup_net RIP: 0010:netdev_exit+0x3f/0x50 Code: 48 8b bb 30 01 00 00 e8 ef 81 b1 ff 48 81 fb c0 3a 54 a1 74 13 48 8b 83 90 00 00 00 48 81 c3 90 00 00 00 48 39 d8 75 02 5b c3 <0f> 0b 5b c3 66 66 2e 0f 1f 84 00 00 00 00 00 66 90 0f 1f 44 00 RSP: 0018:ffffb297079d7e08 EFLAGS: 00010206 RAX: ffff8eb542c00040 RBX: ffff8eb541333150 RCX: 000000008010000d RDX: 000000008010000e RSI: 000000008010000d RDI: ffff8eb440042c00 RBP: ffffb297079d7e48 R08: 0000000000000001 R09: ffffffff9fdeac00 R10: ffff8eb5003be000 R11: 0000000000000001 R12: ffffffffa1545620 R13: ffffffffa1545628 R14: 0000000000000000 R15: ffffffffa1543b20 FS: 0000000000000000(0000) GS:ffff8ed37fa00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005601b5f4c2e8 CR3: 0000001fc8c10002 CR4: 00000000003706e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: ops_exit_list.isra.9+0x36/0x70 cleanup_net+0x234/0x390 process_one_work+0x1cb/0x360 ? process_one_work+0x360/0x360 worker_thread+0x30/0x370 ? process_one_work+0x360/0x360 kthread+0x116/0x130 ? kthread_park+0x80/0x80 ret_from_fork+0x22/0x30 To avoid the above warning and later on the kernel panic that could happen on shutdown due to a NULL pointer dereference, make sure to set the netns_refund flag that was introduced by commit 3a5ca857079e ("can: dev: Move device back to init netns on owning netns delete") to properly restore the IPoIB interfaces to the initial netns.

References

Frequently Asked Questions

What is CVE-2021-47266?
CVE-2021-47266 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-2021-47266?
Upgrading to current release patches (or the latest patched release for your respective branch) resolves the vulnerability.
What is the CVSS score of CVE-2021-47266?
CVE-2021-47266 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-2021-47266?
CVE-2021-47266 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-2021-47266?
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
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-8cxw-6695-4jq3",
  "modified" : "2024-12-26T21:30:35Z",
  "published" : "2024-05-21T15:31:41Z",
  "aliases" : [ "CVE-2021-47266" ],
  "details" : "In the Linux kernel, the following vulnerability has been resolved:\n\nRDMA/ipoib: Fix warning caused by destroying non-initial netns\n\nAfter the commit 5ce2dced8e95 (\"RDMA/ipoib: Set rtnl_link_ops for ipoib\ninterfaces\"), if the IPoIB device is moved to non-initial netns,\ndestroying that netns lets the device vanish instead of moving it back to\nthe initial netns, This is happening because default_device_exit() skips\nthe interfaces due to having rtnl_link_ops set.\n\nSteps to reporoduce:\n  ip netns add foo\n  ip link set mlx5_ib0 netns foo\n  ip netns delete foo\n\nWARNING: CPU: 1 PID: 704 at net/core/dev.c:11435 netdev_exit+0x3f/0x50\nModules linked in: xt_CHECKSUM xt_MASQUERADE xt_conntrack ipt_REJECT\nnf_reject_ipv4 nft_compat nft_counter nft_chain_nat nf_nat nf_conntrack\nnf_defrag_ipv6 nf_defrag_ipv4 nf_tables nfnetlink tun d\n fuse\nCPU: 1 PID: 704 Comm: kworker/u64:3 Tainted: G S      W  5.13.0-rc1+ #1\nHardware name: Dell Inc. PowerEdge R630/02C2CP, BIOS 2.1.5 04/11/2016\nWorkqueue: netns cleanup_net\nRIP: 0010:netdev_exit+0x3f/0x50\nCode: 48 8b bb 30 01 00 00 e8 ef 81 b1 ff 48 81 fb c0 3a 54 a1 74 13 48\n8b 83 90 00 00 00 48 81 c3 90 00 00 00 48 39 d8 75 02 5b c3 <0f> 0b 5b\nc3 66 66 2e 0f 1f 84 00 00 00 00 00 66 90 0f 1f 44 00\nRSP: 0018:ffffb297079d7e08 EFLAGS: 00010206\nRAX: ffff8eb542c00040 RBX: ffff8eb541333150 RCX: 000000008010000d\nRDX: 000000008010000e RSI: 000000008010000d RDI: ffff8eb440042c00\nRBP: ffffb297079d7e48 R08: 0000000000000001 R09: ffffffff9fdeac00\nR10: ffff8eb5003be000 R11: 0000000000000001 R12: ffffffffa1545620\nR13: ffffffffa1545628 R14: 0000000000000000 R15: ffffffffa1543b20\nFS:  0000000000000000(0000) GS:ffff8ed37fa00000(0000) knlGS:0000000000000000\nCS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\nCR2: 00005601b5f4c2e8 CR3: 0000001fc8c10002 CR4: 00000000003706e0\nDR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000\nDR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400\nCall Trace:\n ops_exit_list.isra.9+0x36/0x70\n cleanup_net+0x234/0x390\n process_one_work+0x1cb/0x360\n ? process_one_work+0x360/0x360\n worker_thread+0x30/0x370\n ? process_one_work+0x360/0x360\n kthread+0x116/0x130\n ? kthread_park+0x80/0x80\n ret_from_fork+0x22/0x30\n\nTo avoid the above warning and later on the kernel panic that could happen\non shutdown due to a NULL pointer dereference, make sure to set the\nnetns_refund flag that was introduced by commit 3a5ca857079e (\"can: dev:\nMove device back to init netns on owning netns delete\") to properly\nrestore the IPoIB interfaces to the initial netns.",
  "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-2021-47266"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/0a672f7d89db2da17ae02733ccc08458be72a6f8"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/64f1fb6acc2ab95982fc4334f351d7576c26f313"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/67cf4e447b5e5e9e94996cb6812ae2828e0e0e27"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/a3e74fb9247cd530dca246699d5eb5a691884d32"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-476" ],
    "severity" : "MODERATE",
    "github_reviewed" : false,
    "github_reviewed_at" : null,
    "nvd_published_at" : "2024-05-21T15:15:15Z"
  }
}