CVE-2026-43007

// Conceptual PoC for CVE-2026-43007 // This PoC demonstrates the race condition where a user exits // before the DBC deactivation is handled. #include <fcntl.h> #include <unistd.h> #include <sys/ioctl.h> // Placeholder for actual ioctl codes and definitions #define QAIC_MANAGE_IOCTL 0xABC #define QAIC_ACTIVATE_NETWORK 0x1 int main() { // Step 1: Open the QAIC control device int fd = open("/dev/qaic_control", O_RDWR); if (fd < 0) { return -1; } // Step 2: Activate a network/DBC to allocate resources ioctl(fd, QAIC_ACTIVATE_NETWORK, NULL); // Step 3: Exit immediately without waiting for deactivation handling // This simulates the "owner went away" scenario described in the CVE. // The kernel may not have processed the QAIC_TRANS_DEACTIVATE_FROM_DEV // transaction yet, leaving the DBC resource in a stale state (in_use = true). close(fd); return 0; } // To observe the hang, a subsequent process would need to attempt // to activate a network that results in the device assigning the same DBC ID.

{"cve": {"id": "CVE-2026-43007", "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "published": "2026-05-01T15:16:44.553", "lastModified": "2026-05-07T20:24:32.047", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\naccel/qaic: Handle DBC deactivation if the owner went away\n\nWhen a DBC is released, the device sends a QAIC_TRANS_DEACTIVATE_FROM_DEV\ntransaction to the host over the QAIC_CONTROL MHI channel. QAIC handles\nthis by calling decode_deactivate() to release the resources allocated for\nthat DBC. Since that handling is done in the qaic_manage_ioctl() context,\nif the user goes away before receiving and handling the deactivation, the\nhost will be out-of-sync with the DBCs available for use, and the DBC\nresources will not be freed unless the device is removed. If another user\nloads and requests to activate a network, then the device assigns the same\nDBC to that network, QAIC will \"indefinitely\" wait for dbc->in_use = false,\nleading the user process to hang.\n\nAs a solution to this, handle QAIC_TRANS_DEACTIVATE_FROM_DEV transactions\nthat are received after the user has gone away."}], "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: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": "Primary", "description": [{"lang": "en", "value": "CWE-415"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.4", "versionEndExcluding": "6.6.134", "matchCriteriaId": "C1AFB41D-EE40-4D1A-93ED-E8655E9E65C4"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.7", "versionEndExcluding": "6.12.81", "matchCriteriaId": "6EF80433-B33B-43C5-8E64-0FA7B8DCE1BC"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.13", "versionEndExcluding": "6.18.22", "matchCriteriaId": "C9DF8BCE-36D3-475D-9D21-19E4F02F9029"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.19", "versionEndExcluding": "6.19.12", "matchCriteriaId": "0A2B9540-02D5-41B4-B16A-82AF66FD4F36"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc1:*:*:*:*:*:*", "matchCriteriaId": "F253B622-8837-4245-BCE5-A7BF8FC76A16"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc2:*:*:*:*:*:*", "matchCriteriaId": "4AE85AD8-4641-4E7C-A2F4-305E2CD9EE64"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc3:*:*:*:*:*:*", "matchCriteriaId": "F666C8D8-6538-46D4-B318-87610DE64C34"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc4:*:*:*:*:*:*", "matchCriteriaId": "02259FDA-961B-47BC-AE7F-93D7EC6E90C2"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc5:*:*:*:*:*:*", "matchCriteriaId": "58A9FEFF-C040-420D-8F0A-BFDAAA1DF258"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc6:*:*:*:*:*:*", "matchCriteriaId": "1D2315C0-D46F-4F85-9754-F9E5E11374A6"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/08021f2d4a557d6491e3bcc288e96425f50aa3cf", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/2dd67966f39a2abf8ccb4865031c722e40e01b7f", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/2feec5ae5df785658924ab6bd91280dc3926507c", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/ee0180e77e6c8482644569632065411de844c515", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/f403094d9075d7c565a3d81002b781c325cb3c07", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}]}}