CVE-2026-31690

/* * Conceptual PoC for CVE-2026-31690 * This is a simulation of the vulnerable logic based on the description. * Triggering this requires specific hardware (TH1520) and interaction with the firmware driver. */ #include <stdio.h> #include <stdlib.h> #include <string.h> // Simulating the vulnerable structure interaction struct aon_rpc_data { char data[2]; // Small buffer intended for specific use }; void vulnerable_function(struct aon_rpc_data *resource, int offset) { // Vulnerability: unsafe pointer arithmetic accessing 'mode' // If offset is large enough, this writes past 'data' unsigned int *mode = (unsigned int *)((char *)resource->data + offset); printf("Writing to address: %p\n", mode); *mode = 0xDEADBEEF; // Potential buffer overflow } int main() { struct aon_rpc_data *res = malloc(sizeof(struct aon_rpc_data)); memset(res, 0, sizeof(struct aon_rpc_data)); // Malicious input triggering the overflow (offset > sizeof(data)) // The Smatch warning was "buffer overflow 'data' 2 <= 3" printf("Attempting to trigger overflow...\n"); vulnerable_function(res, 3); free(res); return 0; }

{"cve": {"id": "CVE-2026-31690", "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "published": "2026-04-27T18:16:54.507", "lastModified": "2026-05-06T18:32:01.673", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nfirmware: thead: Fix buffer overflow and use standard endian macros\n\nAddresses two issues in the TH1520 AON firmware protocol driver:\n\n1. Fix a potential buffer overflow where the code used unsafe pointer\n arithmetic to access the 'mode' field through the 'resource' pointer\n with an offset. This was flagged by Smatch static checker as:\n \"buffer overflow 'data' 2 <= 3\"\n\n2. Replace custom RPC_SET_BE* and RPC_GET_BE* macros with standard\n kernel endianness conversion macros (cpu_to_be16, etc.) for better\n portability and maintainability.\n\nThe functionality was re-tested with the GPU power-up sequence,\nconfirming the GPU powers up correctly and the driver probes\nsuccessfully.\n\n[ 12.702370] powervr ffef400000.gpu: [drm] loaded firmware\npowervr/rogue_36.52.104.182_v1.fw\n[ 12.711043] powervr ffef400000.gpu: [drm] FW version v1.0 (build\n6645434 OS)\n[ 12.719787] [drm] Initialized powervr 1.0.0 for ffef400000.gpu on\nminor 0"}], "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-787"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.15", "versionEndExcluding": "6.18.23", "matchCriteriaId": "087D96F9-5A25-4AC4-AA79-B18E87DE65DF"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.19", "versionEndExcluding": "6.19.13", "matchCriteriaId": "1490EF9B-9080-481C-8D22-1306AAE664E4"}, {"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/88c4bd90725557796c15878b7cb70066e9e6b5ab", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/bd15a5deb5a7251dc1a0cf9186f0253f7eacdb97", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/fbdb43f6bb2a15ed382d6eb0ef82c8b07b0d47bb", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}]}}