{"api_version":"1","generated_at":"2026-08-13T12:30:16+00:00","cve":"CVE-2026-68330","urls":{"html":"https://cve.report/CVE-2026-68330","api":"https://cve.report/api/cve/CVE-2026-68330.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-68330","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-68330"},"summary":{"title":"net: airoha: Fix DMA direction for NPU mailbox buffer","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: airoha: Fix DMA direction for NPU mailbox buffer\n\nairoha_npu_send_msg() always maps the mailbox buffer with DMA_TO_DEVICE,\nbut some callers expect the NPU to write response data back into the\nsame buffer:\n\n- airoha_npu_wlan_msg_get() (NPU_OP_GET): NPU writes response into\n  the buffer, then the caller reads it via memcpy()\n- airoha_npu_ppe_stats_setup() (NPU_OP_SET): NPU writes back\n  npu_stats_addr field in the response\n\nOn non-cache-coherent architectures like EN7581 (Cortex-A53 without\nhardware cache coherency for NPU DMA), DMA_TO_DEVICE unmap is a no-op\n— it does not invalidate the CPU cache. If the NPU-written cache line\nis still present in the CPU cache when the caller reads the buffer,\nthe CPU observes stale data instead of the NPU response.\n\nThis is a timing-sensitive bug: small mailbox buffers (~24 bytes)\ntypically fit in a single cache line and may survive in the cache\nuntil the caller reads them, producing silent data corruption rather\nthan a crash. The bug is more likely to trigger when the caller reads\nthe response immediately after dma_unmap_single() without intervening\ncache-evicting operations.\n\nFix by using DMA_BIDIRECTIONAL for both map and unmap, which ensures\ndma_unmap_single() invalidates the CPU cache on non-coherent systems.\nThe mailbox buffers are small so there is no performance concern.","state":"PUBLISHED","assigner":"Linux","published_at":"2026-08-10 13:20:23","updated_at":"2026-08-10 13:20:23"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/76fc5604308a109bf5838c2a0a0eb3ac6819f1ea","name":"https://git.kernel.org/stable/c/76fc5604308a109bf5838c2a0a0eb3ac6819f1ea","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/6f884eb87a79e0c482baef2ad96c96b81d024235","name":"https://git.kernel.org/stable/c/6f884eb87a79e0c482baef2ad96c96b81d024235","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/4c4d866a64f36718cbcdf20add372a599dd44311","name":"https://git.kernel.org/stable/c/4c4d866a64f36718cbcdf20add372a599dd44311","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-68330","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-68330","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected c52918744ee1e49cea86622a2633b9782446428f 76fc5604308a109bf5838c2a0a0eb3ac6819f1ea git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected c52918744ee1e49cea86622a2633b9782446428f 4c4d866a64f36718cbcdf20add372a599dd44311 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected c52918744ee1e49cea86622a2633b9782446428f 6f884eb87a79e0c482baef2ad96c96b81d024235 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6.16","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.16 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.42 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.1.6 7.1.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.2-rc5 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["drivers/net/ethernet/airoha/airoha_npu.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"76fc5604308a109bf5838c2a0a0eb3ac6819f1ea","status":"affected","version":"c52918744ee1e49cea86622a2633b9782446428f","versionType":"git"},{"lessThan":"4c4d866a64f36718cbcdf20add372a599dd44311","status":"affected","version":"c52918744ee1e49cea86622a2633b9782446428f","versionType":"git"},{"lessThan":"6f884eb87a79e0c482baef2ad96c96b81d024235","status":"affected","version":"c52918744ee1e49cea86622a2633b9782446428f","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["drivers/net/ethernet/airoha/airoha_npu.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"6.16"},{"lessThan":"6.16","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.42","versionType":"semver"},{"lessThanOrEqual":"7.1.*","status":"unaffected","version":"7.1.6","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.2-rc5","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.42","versionStartIncluding":"6.16","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.1.6","versionStartIncluding":"6.16","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.2-rc5","versionStartIncluding":"6.16","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: airoha: Fix DMA direction for NPU mailbox buffer\n\nairoha_npu_send_msg() always maps the mailbox buffer with DMA_TO_DEVICE,\nbut some callers expect the NPU to write response data back into the\nsame buffer:\n\n- airoha_npu_wlan_msg_get() (NPU_OP_GET): NPU writes response into\n  the buffer, then the caller reads it via memcpy()\n- airoha_npu_ppe_stats_setup() (NPU_OP_SET): NPU writes back\n  npu_stats_addr field in the response\n\nOn non-cache-coherent architectures like EN7581 (Cortex-A53 without\nhardware cache coherency for NPU DMA), DMA_TO_DEVICE unmap is a no-op\n— it does not invalidate the CPU cache. If the NPU-written cache line\nis still present in the CPU cache when the caller reads the buffer,\nthe CPU observes stale data instead of the NPU response.\n\nThis is a timing-sensitive bug: small mailbox buffers (~24 bytes)\ntypically fit in a single cache line and may survive in the cache\nuntil the caller reads them, producing silent data corruption rather\nthan a crash. The bug is more likely to trigger when the caller reads\nthe response immediately after dma_unmap_single() without intervening\ncache-evicting operations.\n\nFix by using DMA_BIDIRECTIONAL for both map and unmap, which ensures\ndma_unmap_single() invalidates the CPU cache on non-coherent systems.\nThe mailbox buffers are small so there is no performance concern."}],"providerMetadata":{"dateUpdated":"2026-08-10T12:03:06.542Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/76fc5604308a109bf5838c2a0a0eb3ac6819f1ea"},{"url":"https://git.kernel.org/stable/c/4c4d866a64f36718cbcdf20add372a599dd44311"},{"url":"https://git.kernel.org/stable/c/6f884eb87a79e0c482baef2ad96c96b81d024235"}],"title":"net: airoha: Fix DMA direction for NPU mailbox buffer","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-68330","datePublished":"2026-08-10T12:03:06.542Z","dateReserved":"2026-07-30T09:28:09.383Z","dateUpdated":"2026-08-10T12:03:06.542Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-08-10 13:20:23","lastModifiedDate":"2026-08-10 13:20:23","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"68330","Ordinal":"1","Title":"net: airoha: Fix DMA direction for NPU mailbox buffer","CVE":"CVE-2026-68330","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"68330","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: airoha: Fix DMA direction for NPU mailbox buffer\n\nairoha_npu_send_msg() always maps the mailbox buffer with DMA_TO_DEVICE,\nbut some callers expect the NPU to write response data back into the\nsame buffer:\n\n- airoha_npu_wlan_msg_get() (NPU_OP_GET): NPU writes response into\n  the buffer, then the caller reads it via memcpy()\n- airoha_npu_ppe_stats_setup() (NPU_OP_SET): NPU writes back\n  npu_stats_addr field in the response\n\nOn non-cache-coherent architectures like EN7581 (Cortex-A53 without\nhardware cache coherency for NPU DMA), DMA_TO_DEVICE unmap is a no-op\n— it does not invalidate the CPU cache. If the NPU-written cache line\nis still present in the CPU cache when the caller reads the buffer,\nthe CPU observes stale data instead of the NPU response.\n\nThis is a timing-sensitive bug: small mailbox buffers (~24 bytes)\ntypically fit in a single cache line and may survive in the cache\nuntil the caller reads them, producing silent data corruption rather\nthan a crash. The bug is more likely to trigger when the caller reads\nthe response immediately after dma_unmap_single() without intervening\ncache-evicting operations.\n\nFix by using DMA_BIDIRECTIONAL for both map and unmap, which ensures\ndma_unmap_single() invalidates the CPU cache on non-coherent systems.\nThe mailbox buffers are small so there is no performance concern.","Type":"Description","Title":"net: airoha: Fix DMA direction for NPU mailbox buffer"}]}}}