CVE-2026-43281

Description

In the Linux kernel, the following vulnerability has been resolved: mailbox: Prevent out-of-bounds access in fw_mbox_index_xlate() Although it is guided that `#mbox-cells` must be at least 1, there are many instances of `#mbox-cells = <0>;` in the device tree. If that is the case and the corresponding mailbox controller does not provide `fw_xlate` and of_xlate` function pointers, `fw_mbox_index_xlate()` will be used by default and out-of-bounds accesses could occur due to lack of bounds check in that function.

Overview

State: PUBLISHED
Assigner (CNA): Linux
CVSS severity: high
CVSS score: 7.1 / 10
CVSS vector: AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H
Effective score: 7.1 / 10 HIGH source: CNA overview
CWE(s): —
Reserved: 2026-05-01
Published: 2026-05-06 13:29 UTC
Last updated: 2026-05-12 00:21 UTC
Source: https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/43xxx/CVE-2026-43281.json
Linked Threat: CVE-2026-43281 — CVE-2026-43281

NVD triage scoring NVD CVE 2.0

Layer NVD adds on top of the CNA's CVE record — published / last-modified timestamps, exploitability / impact subscores, and the FIRST.org EPSS probability that this CVE will be exploited in the wild in the next 30 days.

NVD published: 2026-05-06 12:16:49 UTC
NVD last modified: 2026-05-08 19:13:43 UTC
NVD CVSS v3.1: 7.1 / 10 HIGH source: nvd@nist.gov
NVD CVSS vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H
Exploitability subscore: 1.8 / 10
Impact subscore: 5.2 / 10
EPSS score: 0.0001 (probability of exploitation in next 30 days)
EPSS percentile: 2.55% vs all CVEs — higher = more likely to be exploited, as of 2026-05-24

NVD-assigned CWE(s): CWE-125 (differs from the CNA list above)

European Union Vulnerability Database ENISA EUVD

ENISA's official EU repository for curated vulnerability intelligence. Carries a separate identifier (EUVD-YYYY-NNNN) and frequently exposes an earlier-published description + CVSS than NVD does.

EUVD ID: EUVD-2026-27680
Assigner: Linux
Published: May 6, 2026, 11:29:02 AM
Updated: May 11, 2026, 10:21:31 PM
EUVD base score: 0.0 / 10
EUVD-reported EPSS: 0.0100
Vendors: Linux
Products: Linux (patch: 0)

Linux (1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <fcd7f96c783626c07ee3ed75fa3739a8a2052310)

Linux (patch: 6.1.167)

Linux (patch: 6.12.77)

Linux (3.18)

Linux (1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <31c4c67dec3362094a6747a171a4848e98542265)

Linux (2b6d83e2b8b7de82331a6a1dcd64b51020a6031c <4caae8168d1b808c7d4ff481295292e3f97f90fb)

Linux (1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <4caae8168d1b808c7d4ff481295292e3f97f90fb)

Linux (1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <2662ed331a69c0b551f78af58f12eb629a89a36f)

Linux (patch: 7.0)

Linux (2b6d83e2b8b7de82331a6a1dcd64b51020a6031c <fcd7f96c783626c07ee3ed75fa3739a8a2052310)

Linux (1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <01d9a8c2615d436b2b30c19c1afe9fcd5726ff6d)

Linux (2b6d83e2b8b7de82331a6a1dcd64b51020a6031c <f50b39fd7c72a8734153644ee945ca0d8b2e65ab)

Linux (2b6d83e2b8b7de82331a6a1dcd64b51020a6031c <01d9a8c2615d436b2b30c19c1afe9fcd5726ff6d)

Linux (2b6d83e2b8b7de82331a6a1dcd64b51020a6031c <31c4c67dec3362094a6747a171a4848e98542265)

Linux (1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <f50b39fd7c72a8734153644ee945ca0d8b2e65ab)

Linux (patch: 6.6.130)

Linux (2b6d83e2b8b7de82331a6a1dcd64b51020a6031c <2662ed331a69c0b551f78af58f12eb629a89a36f)

Linux (patch: 6.19.6)

Linux (patch: 6.18.16)

ENISA description: In the Linux kernel, the following vulnerability has been resolved: mailbox: Prevent out-of-bounds access in fw_mbox_index_xlate() Although it is guided that `#mbox-cells` must be at least 1, there are many instances of `#mbox-cells = <0>;` in the device tree. If that is the case and the corresponding mailbox controller does not provide `fw_xlate` and of_xlate` function pointers, `fw_mbox_index_xlate()` will be used by default and out-of-bounds accesses could occur due to lack of bounds check in that function.

EUVD references (6)

Affected products (2)

Vendor	Product	Versions	Platforms
Linux	Linux	`2b6d83e2b8b7de82331a6a1dcd64b51020a6031c` (affected), `2b6d83e2b8b7de82331a6a1dcd64b51020a6031c` (affected), `2b6d83e2b8b7de82331a6a1dcd64b51020a6031c` (affected), `2b6d83e2b8b7de82331a6a1dcd64b51020a6031c` (affected), `2b6d83e2b8b7de82331a6a1dcd64b51020a6031c` (affected), `2b6d83e2b8b7de82331a6a1dcd64b51020a6031c` (affected)	—
Linux	Linux	`3.18` (affected), `0` (unaffected), `6.1.167` (unaffected), `6.6.130` (unaffected), `6.12.77` (unaffected), `6.18.16` (unaffected), `6.19.6` (unaffected), `7.0` (unaffected)	—

Affected products — CPE 2.3 (8) NVD

NVD's normalized CPE 2.3 matchers, used by vendor tools (vulnerability scanners, asset managers) for automated detection. Compare with the CNA's free-text "Affected products" section above.

cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:3.18:-:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:3.18:rc2:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:3.18:rc3:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:3.18:rc4:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:3.18:rc5:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:3.18:rc6:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:3.18:rc7:*:*:*:*:*:*

Vendor references (6)

References embedded in the original CVE record by the assigning CNA.

MITRE references (6) cveawg.mitre.org

Pulled from MITRE's CVE Services API by the 🛰 Backfill from MITRE button.

Web references (10)

DuckDuckGo results ranked by threat-intel / vendor advisory domains. Generated by the 🔎 Find references (web) button above — same flow as the Remediations search.

https://git.kernel.org/stable/c/2c7ff651ec6b660c7c96a36db9328b3232f555d8 tenable:git.kernel.org
https://git.kernel.org/stable/c/ec0874447895b994182a962d2fee9ef075de5efd tenable:git.kernel.org
https://alas.aws.amazon.com/AL2023/ALAS-2026-1711.html rapid7:alas.aws.amazon.com
https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-27680 rapid7:euvd.enisa.europa.eu
http://cwe.mitre.org/data/definitions/125.html rapid7:cwe.mitre.org
https://attackerkb.com/topics/CVE-2026-43281 rapid7:attackerkb.com
https://alas.aws.amazon.com/AL2023/ALAS-2026-1702.html rapid7:alas.aws.amazon.com
https://www.first.org/epss/ tenable:www.first.org
https://nvd.nist.gov/vuln/detail/CVE-2026-43281 tenable:nvd.nist.gov
https://www.cve.org/CVERecord?id=CVE-2026-43281 tenable:www.cve.org

NVD-tagged references (6)

Reference list NVD curates from the CNA record, vendor advisories, and third-party reports. The tag chips below are NVD's analyst-assigned categories.

https://git.kernel.org/stable/c/01d9a8c2615d436b2b30c19c1afe9fcd5726ff6d 416baaa9-dc9f-4396-8d5f-8c081fb06d67 Patch
https://git.kernel.org/stable/c/2662ed331a69c0b551f78af58f12eb629a89a36f 416baaa9-dc9f-4396-8d5f-8c081fb06d67 Patch
https://git.kernel.org/stable/c/31c4c67dec3362094a6747a171a4848e98542265 416baaa9-dc9f-4396-8d5f-8c081fb06d67 Patch
https://git.kernel.org/stable/c/4caae8168d1b808c7d4ff481295292e3f97f90fb 416baaa9-dc9f-4396-8d5f-8c081fb06d67 Patch
https://git.kernel.org/stable/c/f50b39fd7c72a8734153644ee945ca0d8b2e65ab 416baaa9-dc9f-4396-8d5f-8c081fb06d67 Patch
https://git.kernel.org/stable/c/fcd7f96c783626c07ee3ed75fa3739a8a2052310 416baaa9-dc9f-4396-8d5f-8c081fb06d67 Patch

Remediations (14)

Remediations are stored against the linked Threat row; the list below is deduplicated across both pages.

Microsoft and Adobe Patch Tuesday, April 2026 Security Update Review

web:blog.qualys.com

With Qualys Policy Audit's out-of-the-box mitigation or Compensatory Controls, which reduce the risk of a vulnerability being exploited because the remediation ( fix / patch ) cannot be done immediately, these security controls are not recommended by any industry standards, such as CIS and DISA-STIG.

2026-05-23 21:11 UTC
CISA Warns of Exploited Microsoft Defender 0-Day Flaws

web:cyberpress.org

The U.S. Cybersecurity and Infrastructure Security Agency (CISA) has added two actively exploited Microsoft Defender vulnerabilities to its Known Exploited Vulnerabilities (KEV) catalog, issuing an urgent remediation directive for federal agencies with a due date of June 3, 2026 .

2026-05-23 21:11 UTC
Nvd - Cve-2026-5281

web:nvd.nist.gov

Official websites use .gov A .gov website belongs to an official government organization in the United States.

2026-05-23 21:11 UTC
Security Update Guide - Microsoft

web:portal.msrc.microsoft.com

The Security Update Guide provides information on the latest Microsoft security updates, helping users understand and address potential vulnerabilities effectively.

2026-05-23 21:11 UTC
Microsoft Issues Second Biggest Patch Tuesday Ever in April

web:redmondmag.com

Microsoft April 2026 Patch Tuesday fixed 163 CVEs , marking its second-largest security update. Three zero-day vulnerabilities impacted SharePoint, Chromium-based Edge workflows and Microsoft Defender.

2026-05-23 21:11 UTC
Critical Patches Issued for Microsoft Products, April 14, 2026

web:www.cisecurity.org

<p>Multiple vulnerabilities have been discovered in Microsoft products, the most severe of which could allow for remote code execution. Successful exploitation of the most severe of these vulnerabilities could result in an attacker gaining the same privileges as the logged-on user. Depending on the privileges associated with the user, an attacker could then install programs; view, change, or ...

2026-05-23 21:11 UTC
April 2026 Patch Tuesday: Updates and Analysis | CrowdStrike

web:www.crowdstrike.com

Microsoft's April 2026 Patch Tuesday addresses 164 CVEs , featuring 8 Critical vulnerabilities, one exploited zero-day, and one disclosed zero-day.

2026-05-23 21:11 UTC
Microsoft April 2026 Patch Tuesday fixes 167 ... - Notebookcheck

web:www.notebookcheck.net

Microsoft April 2026 Patch Tuesday fixes 167 vulnerabilities, including an actively exploited SharePoint zero-day. Windows 11 KB5083769 and KB5082052 bring new builds and RDP security.

2026-05-23 21:11 UTC
Microsoft fixes 167 security flaws in April, second biggest Patch ...

web:www.pcworld.com

This month's Patch Tuesday includes an actively exploited Office zero-day vulnerability and several critical RCE bugs in Windows and Remote Desktop.

2026-05-23 21:11 UTC
Microsoft Issues Massive Windows Patch for 160+ Bugs ... - TechRepublic

web:www.techrepublic.com

Microsoft's April 2026 Patch Tuesday fixes 165 vulnerabilities, including two zero-days, in one of the company's largest monthly security updates.

2026-05-23 21:11 UTC
Security Update Guide - Microsoft

web:msrc.microsoft.com

The Microsoft Security Response Center (MSRC) investigates all reports of security vulnerabilities affecting Microsoft products and services, and provides the information here as part of the ongoing effort to help you manage security risks and help keep your systems protected.

2026-05-26 02:47 UTC
Microsoft April 2026 Patch Tuesday fixes 167 flaws, 2 zero-days

web:www.bleepingcomputer.com

Today is Microsoft's April 2026 Patch Tuesday with security updates for 167 flaws, including 2 zero-day vulnerabilities.

2026-05-26 02:47 UTC
Microsoft Confirms Active 0-Day Exploit—Check Emergency Mitigation

web:www.forbes.com

Updated May 17: This article, originally published May 16, has been updated to include further details on the emergency mitigation process recommended after the CVE - 2026 -42897 Microsoft Exchange ...

2026-05-26 02:47 UTC
April 2026 Patch Tuesday | Ivanti

web:www.ivanti.com

April Patch Tuesday is the second-largest Patch Tuesday on record behind the October 2025 Patch Tuesday which resolved 175 CVEs . The lineup includes one zero-day exploit ( CVE - 2026 -3220) and one public disclosure ( CVE - 2026 -33825) and breaks down into 8 Critical, 156 Important, 3 Moderate and 1 Low severity.

2026-05-26 02:47 UTC

AI Forensic Analysis

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Raw JSON

The full cvelistV5 record. Download as CVE-2026-43281.json.

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "drivers/mailbox/mailbox.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "2662ed331a69c0b551f78af58f12eb629a89a36f",
              "status": "affected",
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              "versionType": "git"
            },
            {
              "lessThan": "31c4c67dec3362094a6747a171a4848e98542265",
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            },
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            },
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              "versionType": "git"
            },
            {
              "lessThan": "f50b39fd7c72a8734153644ee945ca0d8b2e65ab",
              "status": "affected",
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              "versionType": "git"
            },
            {
              "lessThan": "fcd7f96c783626c07ee3ed75fa3739a8a2052310",
              "status": "affected",
              "version": "2b6d83e2b8b7de82331a6a1dcd64b51020a6031c",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
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          "programFiles": [
            "drivers/mailbox/mailbox.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "3.18"
            },
            {
              "lessThan": "3.18",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.167",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.130",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.77",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.16",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.19.*",
              "status": "unaffected",
              "version": "6.19.6",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.0",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
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                  "versionStartIncluding": "3.18",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.6.130",
                  "versionStartIncluding": "3.18",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
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                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.16",
                  "versionStartIncluding": "3.18",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.19.6",
                  "versionStartIncluding": "3.18",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.0",
                  "versionStartIncluding": "3.18",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmailbox: Prevent out-of-bounds access in fw_mbox_index_xlate()\n\nAlthough it is guided that `#mbox-cells` must be at least 1, there are\nmany instances of `#mbox-cells = <0>;` in the device tree. If that is\nthe case and the corresponding mailbox controller does not provide\n`fw_xlate` and of_xlate` function pointers, `fw_mbox_index_xlate()` will\nbe used by default and out-of-bounds accesses could occur due to lack of\nbounds check in that function."
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-05-11T22:21:31.452Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/2662ed331a69c0b551f78af58f12eb629a89a36f"
        },
        {
          "url": "https://git.kernel.org/stable/c/31c4c67dec3362094a6747a171a4848e98542265"
        },
        {
          "url": "https://git.kernel.org/stable/c/01d9a8c2615d436b2b30c19c1afe9fcd5726ff6d"
        },
        {
          "url": "https://git.kernel.org/stable/c/4caae8168d1b808c7d4ff481295292e3f97f90fb"
        },
        {
          "url": "https://git.kernel.org/stable/c/f50b39fd7c72a8734153644ee945ca0d8b2e65ab"
        },
        {
          "url": "https://git.kernel.org/stable/c/fcd7f96c783626c07ee3ed75fa3739a8a2052310"
        }
      ],
      "title": "mailbox: Prevent out-of-bounds access in fw_mbox_index_xlate()",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-43281",
    "datePublished": "2026-05-06T11:29:02.278Z",
    "dateReserved": "2026-05-01T14:12:55.998Z",
    "dateUpdated": "2026-05-11T22:21:31.452Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}