CVE-2026-31399

Description

In the Linux kernel, the following vulnerability has been resolved: nvdimm/bus: Fix potential use after free in asynchronous initialization Dingisoul with KASAN reports a use after free if device_add() fails in nd_async_device_register(). Commit b6eae0f61db2 ("libnvdimm: Hold reference on parent while scheduling async init") correctly added a reference on the parent device to be held until asynchronous initialization was complete. However, if device_add() results in an allocation failure the ref count of the device drops to 0 prior to the parent pointer being accessed. Thus resulting in use after free. The bug bot AI correctly identified the fix. Save a reference to the parent pointer to be used to drop the parent reference regardless of the outcome of device_add().

CVSS Details

CVSS Score

7.8

Severity

HIGH

CVSS Vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Configurations (Affected Products)

cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* - VULNERABLE

Linux Kernel < commit 2c638259ad75

Linux Kernel < commit 6fc36c2a925c

Linux Kernel < commit 84af19855d1a

PoC / Exploit Code

⚠ For Security Research Only

The following code is for security research and authorized testing only.

python

/*
 * Conceptual PoC demonstrating the vulnerable logic flow.
 * This is a simplified representation of the bug in nvdimm/bus.c.
 */

#include <linux/device.h>
#include <linux/module.h>

// Simulated vulnerable function structure
void vulnerable_async_register(struct device *dev) {
    int ret;

    // The code attempts to hold a reference, but logic fails on error path
    // if device_add() frees the device immediately.

    // Trigger: device_add fails (e.g., ENOMEM)
    ret = device_add(dev);

    if (ret) {
        // VULNERABILITY: 'dev' might be freed here if refcount drops to 0.
        // Accessing dev->parent leads to Use-After-Free.
        put_device(dev->parent);
        return;
    }

    // Normal cleanup...
    put_device(dev);
}

// Note: Exploiting this requires controlling memory layout to replace
// the freed device object with malicious data.

References

[1] CVE.org https://www.cve.org/CVERecord?id=CVE-2026-31399
[2] NVD NIST https://nvd.nist.gov/vuln/detail/CVE-2026-31399
[3] CVE Details https://www.cvedetails.com/cve/CVE-2026-31399/
[4] VulDB https://vuldb.com/cve/CVE-2026-31399
[5] https://git.kernel.org/stable/c/2c638259ad750833fd46a0cf57672a618542d84c
[6] https://git.kernel.org/stable/c/6fc36c2a925ceaba203eb13d75a8f0879a2c121b
[7] https://git.kernel.org/stable/c/84af19855d1abdee3c9d57c0684e2868e391793c
[8] https://git.kernel.org/stable/c/9a0fb16ba5b372465a3a1ecd761c6fa911a4ab4d
[9] https://git.kernel.org/stable/c/a226e5b49e5fe8c98b14f8507de670189d191348
[10] https://git.kernel.org/stable/c/a36cf138500e56f50db9f9a33222df6969b38326
[11] https://git.kernel.org/stable/c/a8aec14230322ed8f1e8042b6d656c1631d41163
[12] https://git.kernel.org/stable/c/e48bf8f1d2b12c1c5ba1f609edbd4cde5dadc20e

Raw JSON Data

JSON

{"cve": {"id": "CVE-2026-31399", "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "published": "2026-04-03T16:16:38.410", "lastModified": "2026-05-20T12:54:51.920", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnvdimm/bus: Fix potential use after free in asynchronous initialization\n\nDingisoul with KASAN reports a use after free if device_add() fails in\nnd_async_device_register().\n\nCommit b6eae0f61db2 (\"libnvdimm: Hold reference on parent while\nscheduling async init\") correctly added a reference on the parent device\nto be held until asynchronous initialization was complete. However, if\ndevice_add() results in an allocation failure the ref count of the\ndevice drops to 0 prior to the parent pointer being accessed. Thus\nresulting in use after free.\n\nThe bug bot AI correctly identified the fix. Save a reference to the\nparent pointer to be used to drop the parent reference regardless of the\noutcome of device_add()."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Primary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "baseScore": 7.8, "baseSeverity": "HIGH", "attackVector": "LOCAL", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "HIGH"}, "exploitabilityScore": 1.8, "impactScore": 5.9}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-416"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.4.164", "versionEndExcluding": "4.5", "matchCriteriaId": "3F465C16-7558-45C0-8A57-E91446282ED2"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.9.137", "versionEndExcluding": "4.10", "matchCriteriaId": "37605FCB-BF78-48D6-8838-00E69121C271"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.14.81", "versionEndExcluding": "4.15", "matchCriteriaId": "0E3D2C10-16F9-4F31-94C6-EBE99C89FF70"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.18.19", "versionEndExcluding": "4.19", "matchCriteriaId": "9D418973-A1B7-4F79-B990-AFFA8B41983C"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.19.2", "versionEndExcluding": "5.10.253", "matchCriteriaId": "38D904CC-7C9A-4A9A-9A82-96FD6C821BB3"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.11", "versionEndExcluding": "5.15.203", "matchCriteriaId": "20DDB3E9-AABF-4107-ADB0-5362AA067045"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.16", "versionEndExcluding": "6.1.167", "matchCriteriaId": "2EDC6BAF-B710-4E26-B6AA-D68922EE7B43"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.2", "versionEndExcluding": "6.6.130", "matchCriteriaId": "C57BB918-DF28-46B3-94F7-144176841267"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.7", "versionEndExcluding": "6.12.78", "matchCriteriaId": "28D591F5-B196-4CC9-905C-DC80F116E7A8"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.13", "versionEndExcluding": "6.18.20", "matchCriteriaId": "E5571059-6552-48E7-9BEF-3E358C387171"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.19", "versionEndExcluding": "6.19.10", "matchCriteriaId": "96D34333-38BE-4414-9E79-6EB764329581"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc1:*:*:*:*:*:*", "matchCriteriaId": "F253B622-8837-4245-BCE5-A7BF8FC76A16"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc2:*:*:*:*:*:*", "matchCriteriaId": "4AE85AD8-4641-4E7C-A2F4-305E2CD9EE64"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc3:*:*:*:*:*:*", "matchCriteriaId": "F666C8D8-6538-46D4-B318-87610DE64C34"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc4:*:*:*:*:*:*", "matchCriteriaId": "02259FDA-961B-47BC-AE7F-93D7EC6E90C2"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/2c638259ad750833fd46a0cf57672a618542d84c", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/6fc36c2a925ceaba203eb13d75a8f0879a2c121b", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/84af19855d1abdee3 ... (truncated)