CVE-2026-43172

Description

In the Linux kernel, the following vulnerability has been resolved: wifi: iwlwifi: fix 22000 series SMEM parsing If the firmware were to report three LMACs (which doesn't exist in hardware) then using "fwrt->smem_cfg.lmac[2]" is an overrun of the array. Reject such and use IWL_FW_CHECK instead of WARN_ON in this function.

CVSS Details

CVSS Score

8.8

Severity

HIGH

CVSS Vector

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

Configurations (Affected Products)

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

Linux Kernel (修复提交之前的主线版本)

Linux Kernel 6.x (具体受影响版本需参考Git修复提交 c/1d49a42717bdc8de77eabeb5b7d3e88d141ffea9)

PoC / Exploit Code

⚠ For Security Research Only

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

python

/**
 * PoC Concept for CVE-2026-43172
 * Triggering the bug requires a modified firmware image or
 * a tool to inject malformed SMEM data to the iwlwifi driver.
 * This C code simulates the missing bounds check logic.
 */

#include <stdio.h>
#include <stdlib.h>

#define MAX_LMACS 2

struct smem_cfg {
    int lmac[MAX_LMACS];
};

// Simulated vulnerable function
void iwl_parse_smem(struct smem_cfg *cfg, int num_lmacs) {
    printf("Parsing SMEM with %d LMACs\n", num_lmacs);
    
    // VULNERABILITY: Missing check for (num_lmacs > MAX_LMACS)
    // If num_lmacs is 3, accessing lmac[2] is an out-of-bounds read/write.
    if (num_lmacs > 0) {
        int val = cfg->lmac[num_lmacs - 1]; // Out of bounds here if num_lmacs > 2
        printf("Accessed lmac[%d] = %d\n", num_lmacs - 1, val);
    }
}

int main() {
    struct smem_cfg my_cfg = {0};
    
    // Normal case: 2 LMACs
    iwl_parse_smem(&my_cfg, 2);
    
    // Trigger case: 3 LMACs (Causes array overrun)
    printf("\nTriggering Vulnerability:\n");
    iwl_parse_smem(&my_cfg, 3);
    
    return 0;
}

References

[1] CVE.org https://www.cve.org/CVERecord?id=CVE-2026-43172
[2] NVD NIST https://nvd.nist.gov/vuln/detail/CVE-2026-43172
[3] CVE Details https://www.cvedetails.com/cve/CVE-2026-43172/
[4] VulDB https://vuldb.com/cve/CVE-2026-43172
[5] https://git.kernel.org/stable/c/1d49a42717bdc8de77eabeb5b7d3e88d141ffea9
[6] https://git.kernel.org/stable/c/2b4b1510aaaf5b9fb57327ecffc20c055f61f205
[7] https://git.kernel.org/stable/c/58192b9ce09b0f0f86e2036683bd542130b91a98

Raw JSON Data

JSON

{"cve": {"id": "CVE-2026-43172", "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "published": "2026-05-06T12:16:35.583", "lastModified": "2026-05-13T14:56:38.797", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nwifi: iwlwifi: fix 22000 series SMEM parsing\n\nIf the firmware were to report three LMACs (which doesn't\nexist in hardware) then using \"fwrt->smem_cfg.lmac[2]\" is\nan overrun of the array. Reject such and use IWL_FW_CHECK\ninstead of WARN_ON in this function."}], "metrics": {"cvssMetricV31": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "baseScore": 8.8, "baseSeverity": "HIGH", "attackVector": "ADJACENT_NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "HIGH"}, "exploitabilityScore": 2.8, "impactScore": 5.9}]}, "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": "5.8", "versionEndExcluding": "6.18.16", "matchCriteriaId": "6F6A9564-8939-4C1F-8042-65035D578DD8"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.19", "versionEndExcluding": "6.19.6", "matchCriteriaId": "373EEEDA-FAA1-4FB4-B6ED-DB4DD99DBE67"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/1d49a42717bdc8de77eabeb5b7d3e88d141ffea9", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/2b4b1510aaaf5b9fb57327ecffc20c055f61f205", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/58192b9ce09b0f0f86e2036683bd542130b91a98", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}]}}