CVE-2026-31784

/* * Conceptual Proof of Concept (PoC) for CVE-2026-31784 * This C code demonstrates the logical flaw present in the Linux Kernel's drm/xe/pxp module. * The vulnerable function fails to clear a restart flag after jumping back, * causing an infinite loop. */ #include <stdio.h> #include <stdbool.h> void simulated_vulnerable_function() { bool restart_flag = false; int counter = 0; start: printf("Function started. Counter: %d\n", counter); // Simulate some internal logic if (counter > 0) { printf("Checking restart flag...\n"); // VULNERABILITY: In the actual CVE, the code path that leads to 'start' // does not reset 'restart_flag'. If it remains true, we loop forever. if (restart_flag) { printf("Restart flag is still TRUE. Jumping back...\n"); goto start; } } // Simulate a condition that triggers a restart (e.g., initialization retry) if (counter == 0) { restart_flag = true; // Set the flag counter++; printf("Condition met. Setting restart flag and jumping...\n"); goto start; // EXPLOIT: The jump happens, but the flag remains true for the next iteration. } printf("Function finished normally.\n"); } int main() { printf("Starting PoC simulation for CVE-2026-31784...\n"); simulated_vulnerable_function(); return 0; }

{"cve": {"id": "CVE-2026-31784", "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "published": "2026-05-01T15:16:41.923", "lastModified": "2026-05-12T15:09:18.907", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ndrm/xe/pxp: Clear restart flag in pxp_start after jumping back\n\nIf we don't clear the flag we'll keep jumping back at the beginning of\nthe function once we reach the end.\n\n(cherry picked from commit 0850ec7bb2459602351639dccf7a68a03c9d1ee0)"}], "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": "NVD-CWE-noinfo"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.17", "versionEndExcluding": "6.18.22", "matchCriteriaId": "BAFCD467-09C6-4175-86E9-C7D4ED97987D"}, {"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/400ee45f80480c05c3fa673967f25faab8323753", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/76903b2057c8677c2c006e87fede15f496555dc0", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/9e962e68a9d26135af67c423767c0983d9ad94c3", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}]}}