CVE-2026-43250

Description

In the Linux kernel, the following vulnerability has been resolved: usb: chipidea: udc: fix DMA and SG cleanup in _ep_nuke() The ChipIdea UDC driver can encounter "not page aligned sg buffer" errors when a USB device is reconnected after being disconnected during an active transfer. This occurs because _ep_nuke() returns requests to the gadget layer without properly unmapping DMA buffers or cleaning up scatter-gather bounce buffers. Root cause: When a disconnect happens during a multi-segment DMA transfer, the request's num_mapped_sgs field and sgt.sgl pointer remain set with stale values. The request is returned to the gadget driver with status -ESHUTDOWN but still has active DMA state. If the gadget driver reuses this request on reconnect without reinitializing it, the stale DMA state causes _hardware_enqueue() to skip DMA mapping (seeing non-zero num_mapped_sgs) and attempt to use freed/invalid DMA addresses, leading to alignment errors and potential memory corruption. The normal completion path via _hardware_dequeue() properly calls usb_gadget_unmap_request_by_dev() and sglist_do_debounce() before returning the request. The _ep_nuke() path must do the same cleanup to ensure requests are returned in a clean, reusable state. Fix: Add DMA unmapping and bounce buffer cleanup to _ep_nuke() to mirror the cleanup sequence in _hardware_dequeue(): - Call usb_gadget_unmap_request_by_dev() if num_mapped_sgs is set - Call sglist_do_debounce() with copy=false if bounce buffer exists This ensures that when requests are returned due to endpoint shutdown, they don't retain stale DMA mappings. The 'false' parameter to sglist_do_debounce() prevents copying data back (appropriate for shutdown path where transfer was aborted).

Overview

State: PUBLISHED
Assigner (CNA): Linux
CVSS severity: high
CVSS score: 7.8 / 10
CVSS vector: AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Effective score: 7.8 / 10 HIGH source: CNA overview
MSRC score: 7.1 / 10 HIGH MS rating: Moderate
CWE(s): CWE-787
Reserved: 2026-05-01
Published: 2026-05-06 13:28 UTC
Last updated: 2026-05-12 00:20 UTC
Source: https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/43xxx/CVE-2026-43250.json
Linked Threat: CVE-2026-43250 — CVE-2026-43250

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 12:16:45 UTC
NVD last modified: 2026-05-12 18:51:16 UTC
NVD CVSS v3.1: 7.8 / 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:H/A:H
Exploitability subscore: 1.8 / 10
Impact subscore: 5.9 / 10
EPSS score: 0.0002 (probability of exploitation in next 30 days)
EPSS percentile: 3.78% vs all CVEs — higher = more likely to be exploited, as of 2026-05-24

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-2026-27813
Assigner: Linux
Published: May 6, 2026, 11:28:41 AM
Updated: May 11, 2026, 10:20:54 PM
EUVD base score: 0.0 / 10
EUVD-reported EPSS: 0.0200
Vendors: Linux
Products: Linux (1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <f4fbf2d4750d12ac8525d2efac1016fa0d84d4ec)

Linux (1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <cea2a1257a3b5ea3e769a445b34af13e6aa5a123)

Linux (patch: 0)

Linux (2.6.29)

Linux (aa69a8093ff985873cb44fe1157bd6db29a20fe4 <f4fbf2d4750d12ac8525d2efac1016fa0d84d4ec)

Linux (patch: 6.12.75)

Linux (1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <e74c436f8568af1c60942469d0a2300b3ada3857)

Linux (1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <1b72b834511d17f4d069d512f78671f3f210a2f1)

Linux (patch: 6.18.16)

Linux (aa69a8093ff985873cb44fe1157bd6db29a20fe4 <cea2a1257a3b5ea3e769a445b34af13e6aa5a123)

Linux (patch: 6.19.6)

Linux (aa69a8093ff985873cb44fe1157bd6db29a20fe4 <1b72b834511d17f4d069d512f78671f3f210a2f1)

Linux (aa69a8093ff985873cb44fe1157bd6db29a20fe4 <e74c436f8568af1c60942469d0a2300b3ada3857)

Linux (patch: 7.0)

ENISA description: In the Linux kernel, the following vulnerability has been resolved: usb: chipidea: udc: fix DMA and SG cleanup in _ep_nuke() The ChipIdea UDC driver can encounter "not page aligned sg buffer" errors when a USB device is reconnected after being disconnected during an active transfer. This occurs because _ep_nuke() returns requests to the gadget layer without properly unmapping DMA buffers or cleaning up scatter-gather bounce buffers. Root cause: When a disconnect happens during a multi-segment DMA transfer, the request's num_mapped_sgs field and sgt.sgl pointer remain set with stale values. The request is returned to the gadget driver with status -ESHUTDOWN but still has active DMA state. If the gadget driver reuses this request on reconnect without reinitializing it, the stale DMA state causes _hardware_enqueue() to skip DMA mapping (seeing non-zero num_mapped_sgs) and attempt to use freed/invalid DMA addresses, leading to alignment errors and potential memory corruption. The normal completion path via _hardware_dequeue() properly calls usb_gadget_unmap_request_by_dev() and sglist_do_debounce() before returning the request. The _ep_nuke() path must do the same cleanup to ensure requests are returned in a clean, reusable state. Fix: Add DMA unmapping and bounce buffer cleanup to _ep_nuke() to mirror the cleanup sequence in _hardware_dequeue(): - Call usb_gadget_unmap_request_by_dev() if num_mapped_sgs is set - Call sglist_do_debounce() with copy=false if bounce buffer exists This ensures that when requests are returned due to endpoint shutdown, they don't retain stale DMA mappings. The 'false' parameter to sglist_do_debounce() prevents copying data back (appropriate for shutdown path where transfer was aborted).

EUVD references (4)

Microsoft Security Response Center MSRC

Microsoft's vendor-authoritative record from the Security Update Guide — its own CVSS score, impact, severity rating, exploit assessment, and KB-article fixes. Refreshed 2026-08-12 01:09 UTC (source: CVRF).

MS severity: Moderate
MS CVSS base score: 7.1 / 10 (temporal 6.5)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H/E:U
Release: 2026-May

Affected products (2)

Vendor	Product	Versions	Platforms
Linux	Linux	`aa69a8093ff985873cb44fe1157bd6db29a20fe4` (affected), `aa69a8093ff985873cb44fe1157bd6db29a20fe4` (affected), `aa69a8093ff985873cb44fe1157bd6db29a20fe4` (affected), `aa69a8093ff985873cb44fe1157bd6db29a20fe4` (affected)	—
Linux	Linux	`2.6.29` (affected), `0` (unaffected), `6.12.75` (unaffected), `6.18.16` (unaffected), `6.19.6` (unaffected), `7.0` (unaffected)	—

Affected products — CPE 2.3 (1) 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:*:*:*:*:*:*:*:*

Vendor references (4)

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

MITRE references (4) cveawg.mitre.org

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

Web references (4)

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

MSRC update guide: CVE-2026-43250 msrc
https://www.first.org/epss/ tenable:www.first.org
https://nvd.nist.gov/vuln/detail/CVE-2026-43250 tenable:nvd.nist.gov
https://www.cve.org/CVERecord?id=CVE-2026-43250 tenable:www.cve.org

NVD-tagged references (4)

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/1b72b834511d17f4d069d512f78671f3f210a2f1 416baaa9-dc9f-4396-8d5f-8c081fb06d67 Patch
https://git.kernel.org/stable/c/cea2a1257a3b5ea3e769a445b34af13e6aa5a123 416baaa9-dc9f-4396-8d5f-8c081fb06d67 Patch
https://git.kernel.org/stable/c/e74c436f8568af1c60942469d0a2300b3ada3857 416baaa9-dc9f-4396-8d5f-8c081fb06d67 Patch
https://git.kernel.org/stable/c/f4fbf2d4750d12ac8525d2efac1016fa0d84d4ec 416baaa9-dc9f-4396-8d5f-8c081fb06d67 Patch

Remediations (15)

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
Patch Tuesday, April 2026 Edition - Krebs on Security

web:krebsonsecurity.com

For a clickable, per- patch breakdown, check out the SANS Internet Storm Center Patch Tuesday roundup. Running into problems applying any of these updates?

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
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.

2026-05-23 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 Confirms Global SharePoint Attack — Emergency ... - Forbes

web:www.forbes.com

Microsoft has confirmed that SharePoint Server is under mass global attack. Breaking: An emergency patch has now been released — update immediately.

2026-05-23 21:11 UTC
Oracle Critical Patch Update Advisory - April 2026

web:www.oracle.com

This Critical Patch Update contains 481 new security patches across the product families listed below. Please note that an MOS note summarizing the content of this Critical Patch Update and other Oracle Software Security Assurance activities is located at April 2026 Critical Patch Update: Executive Summary and Analysis.

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
Patch Tuesday - April 2026 - Rapid7

web:www.rapid7.com

Microsoft is publishing 167 vulnerabilities on April 2026 Patch Tuesday, including an exploited-in-the-wild SharePoint vuln.

2026-05-23 21:11 UTC
Security Advisory Bulletin 064 | Ubiquiti Community

web:community.ui.com

Published: May 21, 2026 Updated: May 22, 2026 Version: 1.1 Revision: 1.1 Summary 1 of 5 A malicious actor with access to the network and high privileges could exploit an Improper Input Validation vulnerability found in UniFi OS devices to execute a Command Injection. Affected Products: UniFi OS Server (Version 5.0.6 and earlier) Mitigation : Update your UniFi OS Server to Version 5.0.8 or later ...

2026-05-26 02:47 UTC
Microsoft Patch Tuesday March 2026 - 78 Vulnerabilities Fixed ...

web:cybersecuritynews.com

Microsoft released its March 2026 Patch Tuesday security update on March 10, 2026 , addressing 78 vulnerabilities across Windows, Microsoft Office, Azure, SQL Server, and .NET. The update includes one actively exploited zero-day vulnerability and multiple Critical-rated flaws demanding immediate attention from security teams. The most urgent fix this month is CVE - 2026 -21262, the sole zero-day ...

2026-05-26 02:47 UTC
Security Update Guide - Microsoft Security Response Center

web:msrc.microsoft.com

Security Update Guide - Microsoft Security Response Center

2026-05-26 02:47 UTC
Landing Page | ServiceNow Common Vulnerabilities & Exposures (CVE ...

web:support.servicenow.com

Overview The advisories below document publicly disclosed Common Vulnerabilities and Exposures ( CVEs ) in the Now Platform by ServiceNow. Because ServiceNow uses various methods to communicate vulnerability information, patches, and other fixes, customers should review family, security patch , and hotfix release notes, which are available at https://docs.servicenow.com, for a complete list of ...

2026-05-26 02:47 UTC
Patch Tuesday May 2026: Security Updates & CVE Analysis

web:zecurit.com

Get the complete breakdown of Microsoft's May 2026 Patch Tuesday. We analyze the latest security updates and all critical CVEs .

2026-05-26 02:47 UTC

AI Forensic Analysis

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Raw JSON

The full cvelistV5 record. Download as CVE-2026-43250.json.

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "drivers/usb/chipidea/udc.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "1b72b834511d17f4d069d512f78671f3f210a2f1",
              "status": "affected",
              "version": "aa69a8093ff985873cb44fe1157bd6db29a20fe4",
              "versionType": "git"
            },
            {
              "lessThan": "f4fbf2d4750d12ac8525d2efac1016fa0d84d4ec",
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              "versionType": "git"
            },
            {
              "lessThan": "e74c436f8568af1c60942469d0a2300b3ada3857",
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              "version": "aa69a8093ff985873cb44fe1157bd6db29a20fe4",
              "versionType": "git"
            },
            {
              "lessThan": "cea2a1257a3b5ea3e769a445b34af13e6aa5a123",
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              "versionType": "git"
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          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
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          ],
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          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "2.6.29"
            },
            {
              "lessThan": "2.6.29",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.75",
              "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:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.75",
                  "versionStartIncluding": "2.6.29",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.16",
                  "versionStartIncluding": "2.6.29",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.19.6",
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                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.0",
                  "versionStartIncluding": "2.6.29",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nusb: chipidea: udc: fix DMA and SG cleanup in _ep_nuke()\n\nThe ChipIdea UDC driver can encounter \"not page aligned sg buffer\"\nerrors when a USB device is reconnected after being disconnected\nduring an active transfer. This occurs because _ep_nuke() returns\nrequests to the gadget layer without properly unmapping DMA buffers\nor cleaning up scatter-gather bounce buffers.\n\nRoot cause:\nWhen a disconnect happens during a multi-segment DMA transfer, the\nrequest's num_mapped_sgs field and sgt.sgl pointer remain set with\nstale values. The request is returned to the gadget driver with status\n-ESHUTDOWN but still has active DMA state. If the gadget driver reuses\nthis request on reconnect without reinitializing it, the stale DMA\nstate causes _hardware_enqueue() to skip DMA mapping (seeing non-zero\nnum_mapped_sgs) and attempt to use freed/invalid DMA addresses,\nleading to alignment errors and potential memory corruption.\n\nThe normal completion path via _hardware_dequeue() properly calls\nusb_gadget_unmap_request_by_dev() and sglist_do_debounce() before\nreturning the request. The _ep_nuke() path must do the same cleanup\nto ensure requests are returned in a clean, reusable state.\n\nFix:\nAdd DMA unmapping and bounce buffer cleanup to _ep_nuke() to mirror\nthe cleanup sequence in _hardware_dequeue():\n- Call usb_gadget_unmap_request_by_dev() if num_mapped_sgs is set\n- Call sglist_do_debounce() with copy=false if bounce buffer exists\n\nThis ensures that when requests are returned due to endpoint shutdown,\nthey don't retain stale DMA mappings. The 'false' parameter to\nsglist_do_debounce() prevents copying data back (appropriate for\nshutdown path where transfer was aborted)."
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-05-11T22:20:54.786Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
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          "url": "https://git.kernel.org/stable/c/1b72b834511d17f4d069d512f78671f3f210a2f1"
        },
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          "url": "https://git.kernel.org/stable/c/f4fbf2d4750d12ac8525d2efac1016fa0d84d4ec"
        },
        {
          "url": "https://git.kernel.org/stable/c/e74c436f8568af1c60942469d0a2300b3ada3857"
        },
        {
          "url": "https://git.kernel.org/stable/c/cea2a1257a3b5ea3e769a445b34af13e6aa5a123"
        }
      ],
      "title": "usb: chipidea: udc: fix DMA and SG cleanup in _ep_nuke()",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-43250",
    "datePublished": "2026-05-06T11:28:41.158Z",
    "dateReserved": "2026-05-01T14:12:55.996Z",
    "dateUpdated": "2026-05-11T22:20:54.786Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}