CVE-2026-20687

/* * Conceptual PoC for Use-After-Free in Kernel Memory * This code demonstrates the logic of a UAF vulnerability. * Exploiting this in a real scenario requires heap grooming. */ #include <stdio.h> #include <stdlib.h> #include <string.h> // Simulating kernel object structure typedef struct _KernelObject { int id; char buffer[64]; void (*callback)(void); } KernelObject; // Malicious callback function to simulate kernel memory write/code execution void malicious_payload() { printf("[+] Exploit triggered: Executing arbitrary code in kernel context.\n"); // Hypothetical kernel memory write or privilege escalation } int main(int argc, char **argv) { printf("[*] Simulating CVE-2026-20687 PoC...\n"); // Step 1: Allocate kernel object KernelObject *k_obj = (KernelObject *)malloc(sizeof(KernelObject)); k_obj->id = 1; k_obj->callback = NULL; printf("[*] Kernel Object allocated at: %p\n", (void *)k_obj); // Step 2: Free the object (Vulnerability trigger: pointer not cleared) free(k_obj); printf("[*] Object freed.\n"); // Step 3: Heap Spray / Re-allocation to control freed memory // Attacker allocates memory that overlaps with the freed k_obj printf("[*] Attacker spraying heap to reclaim memory...\n"); char *fake_data = (char *)malloc(sizeof(KernelObject)); // Simulating the memory overlap (In real exploit, this requires precise timing) if ((void *)fake_data == (void *)k_obj) { printf("[+] Successfully reclaimed freed memory address.\n"); // Craft the fake object KernelObject *fake_obj = (KernelObject *)fake_data; fake_obj->callback = malicious_payload; printf("[*] malicious payload written to freed memory.\n"); // Step 4: Use-After-Free trigger // The kernel erroneously uses the freed pointer if (k_obj->callback != NULL) { printf("[*] Kernel calling virtual function via dangling pointer...\n"); k_obj->callback(); // Triggers malicious_payload } } else { printf("[-] Heap spray failed to reclaim specific address.\n"); } free(fake_data); return 0; }

{"cve": {"id": "CVE-2026-20687", "sourceIdentifier": "[email protected]", "published": "2026-03-25T01:17:05.587", "lastModified": "2026-03-25T20:07:15.087", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "A use after free issue was addressed with improved memory management. This issue is fixed in iOS 18.7.7 and iPadOS 18.7.7, iOS 26.4 and iPadOS 26.4, macOS Sequoia 15.7.5, macOS Tahoe 26.4, tvOS 26.4, watchOS 26.4. An app may be able to cause unexpected system termination or write kernel memory."}, {"lang": "es", "value": "Se abordó un problema de uso después de liberar con una gestión de memoria mejorada. Este problema está solucionado en iOS 18.7.7 y iPadOS 18.7.7, iOS 26.4 y iPadOS 26.4, macOS Sequoia 15.7.5, macOS Tahoe 26.4, tvOS 26.4, watchOS 26.4. Una app podría causar una terminación inesperada del sistema o escribir en la memoria del kernel."}], "metrics": {"cvssMetricV31": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:H", "baseScore": 7.1, "baseSeverity": "HIGH", "attackVector": "LOCAL", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "REQUIRED", "scope": "UNCHANGED", "confidentialityImpact": "NONE", "integrityImpact": "HIGH", "availabilityImpact": "HIGH"}, "exploitabilityScore": 1.8, "impactScore": 5.2}]}, "weaknesses": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-416"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:apple:ipados:*:*:*:*:*:*:*:*", "versionEndExcluding": "18.7.7", "matchCriteriaId": "118313FD-8CF6-4412-B1A8-4BC3D5C2F519"}, {"vulnerable": true, "criteria": "cpe:2.3:o:apple:ipados:*:*:*:*:*:*:*:*", "versionStartIncluding": "26.0", "versionEndExcluding": "26.4", "matchCriteriaId": "F201257D-2F7C-43AA-BD51-ED5EC98F99E0"}, {"vulnerable": true, "criteria": "cpe:2.3:o:apple:iphone_os:*:*:*:*:*:*:*:*", "versionEndExcluding": "18.7.7", "matchCriteriaId": "684E10EB-D01A-4E80-8764-B48B554B0B5E"}, {"vulnerable": true, "criteria": "cpe:2.3:o:apple:iphone_os:*:*:*:*:*:*:*:*", "versionStartIncluding": "26.0", "versionEndExcluding": "26.4", "matchCriteriaId": "F7F08C35-7A60-4FEC-8D44-533902F43EDD"}, {"vulnerable": true, "criteria": "cpe:2.3:o:apple:macos:*:*:*:*:*:*:*:*", "versionStartIncluding": "15.0", "versionEndExcluding": "15.7.5", "matchCriteriaId": "DD21D2C9-BBEC-4E8E-B8D2-C92B7E6155E1"}, {"vulnerable": true, "criteria": "cpe:2.3:o:apple:macos:*:*:*:*:*:*:*:*", "versionStartIncluding": "26.0", "versionEndExcluding": "26.4", "matchCriteriaId": "6CF848CD-25D4-4371-BEF3-1ACCE47AD81F"}, {"vulnerable": true, "criteria": "cpe:2.3:o:apple:tvos:*:*:*:*:*:*:*:*", "versionEndExcluding": "26.4", "matchCriteriaId": "A906E2B7-B83B-4AD0-B00F-BEDEF2EDB844"}, {"vulnerable": true, "criteria": "cpe:2.3:o:apple:watchos:*:*:*:*:*:*:*:*", "versionEndExcluding": "26.4", "matchCriteriaId": "F6EAF0A5-7CFF-4EF6-9BC7-DB25B213F753"}]}]}], "references": [{"url": "https://support.apple.com/en-us/126792", "source": "[email protected]", "tags": ["Release Notes", "Vendor Advisory"]}, {"url": "https://support.apple.com/en-us/126793", "source": "[email protected]", "tags": ["Release Notes", "Vendor Advisory"]}, {"url": "https://support.apple.com/en-us/126794", "source": "[email protected]", "tags": ["Release Notes", "Vendor Advisory"]}, {"url": "https://support.apple.com/en-us/126795", "source": "[email protected]", "tags": ["Release Notes", "Vendor Advisory"]}, {"url": "https://support.apple.com/en-us/126797", "source": "[email protected]", "tags": ["Release Notes", "Vendor Advisory"]}, {"url": "https://support.apple.com/en-us/126798", "source": "[email protected]", "tags": ["Release Notes", "Vendor Advisory"]}]}}