{"id":"CVE-2026-68194","state":"PUBLISHED","title":"wifi: mt76: mt7921: drop TXRX_NOTIFY on non-mmio buses","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nwifi: mt76: mt7921: drop TXRX_NOTIFY on non-mmio buses\n\nPKT_TYPE_TXRX_NOTIFY is an mmio-only event, but mt7921_rx_check() and\nmt7921_queue_rx_skb() dispatch it to mt7921_mac_tx_free() on every bus.\nmt7921_mac_tx_free() cleans the DMA tx queues with\nmt76_queue_tx_cleanup(), which calls queue_ops->tx_cleanup(). Only the\nmmio queue ops implement that callback; on USB and SDIO it is NULL, so\na TXRX_NOTIFY there calls a NULL pointer in the RX worker:\n\n  BUG: kernel NULL pointer dereference, address: 0000000000000000\n  RIP: 0010:0x0\n  Call Trace:\n   mt7921_mac_tx_free+0x64/0x310 [mt7921_common]\n   mt7921_rx_check+0x5f/0xf0 [mt7921_common]\n   mt76u_rx_worker+0x1b9/0x620 [mt76_usb]\n\nDrop the event on non-mmio buses via mt76_is_mmio(), as in\ncommit 5683e1488aa9 (\"wifi: mt76: connac: do not check WED status for\nnon-mmio devices\").","publishedAt":"2026-08-10T12:00:12.245Z","updatedAt":"2026-08-19T16:31:09.017Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"48fab5bbef4092d925ab3214773ad12e68807223","status":"affected","lessThan":"7003a2cbddd7917933c1f169c7874cfa6ab852c3","versionType":"git"},{"version":"48fab5bbef4092d925ab3214773ad12e68807223","status":"affected","lessThan":"ef2ee5f820c3ef87643b51e960c20b4a14d8336b","versionType":"git"},{"version":"48fab5bbef4092d925ab3214773ad12e68807223","status":"affected","lessThan":"ecf995b828191829ba4a87169bccabcbeb5c9c32","versionType":"git"},{"version":"48fab5bbef4092d925ab3214773ad12e68807223","status":"affected","lessThan":"263816e92e8d66c81c98ccab2b5d2191ed08ec71","versionType":"git"},{"version":"48fab5bbef4092d925ab3214773ad12e68807223","status":"affected","lessThan":"24475d2ddc8d8dfd82f4d2be0d951401f86911a6","versionType":"git"},{"version":"48fab5bbef4092d925ab3214773ad12e68807223","status":"affected","lessThan":"da4082e91acabc1498611ed8ccc53f0610baefc6","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/net/wireless/mediatek/mt76/mt7921/mac.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.16","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.16","versionType":"semver"},{"version":"6.1.183","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.148","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.101","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.42","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.6","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/net/wireless/mediatek/mt76/mt7921/mac.c"]}],"references":["https://git.kernel.org/stable/c/7003a2cbddd7917933c1f169c7874cfa6ab852c3","https://git.kernel.org/stable/c/ef2ee5f820c3ef87643b51e960c20b4a14d8336b","https://git.kernel.org/stable/c/ecf995b828191829ba4a87169bccabcbeb5c9c32","https://git.kernel.org/stable/c/263816e92e8d66c81c98ccab2b5d2191ed08ec71","https://git.kernel.org/stable/c/24475d2ddc8d8dfd82f4d2be0d951401f86911a6","https://git.kernel.org/stable/c/da4082e91acabc1498611ed8ccc53f0610baefc6"],"weaknesses":[],"ingestedAt":"2026-10-29T20:12:49.727Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/68xxx/CVE-2026-68194.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-68194","state":"PUBLISHED","datePublished":"2026-08-10T12:00:12.245Z","dateUpdated":"2026-08-19T16:31:09.017Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-07-30T09:28:09.374Z"},"containers":{"cna":{"title":"wifi: mt76: mt7921: drop TXRX_NOTIFY on non-mmio buses","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nwifi: mt76: mt7921: drop TXRX_NOTIFY on non-mmio buses\n\nPKT_TYPE_TXRX_NOTIFY is an mmio-only event, but mt7921_rx_check() and\nmt7921_queue_rx_skb() dispatch it to mt7921_mac_tx_free() on every bus.\nmt7921_mac_tx_free() cleans the DMA tx queues with\nmt76_queue_tx_cleanup(), which calls queue_ops->tx_cleanup(). Only the\nmmio queue ops implement that callback; on USB and SDIO it is NULL, so\na TXRX_NOTIFY there calls a NULL pointer in the RX worker:\n\n  BUG: kernel NULL pointer dereference, address: 0000000000000000\n  RIP: 0010:0x0\n  Call Trace:\n   mt7921_mac_tx_free+0x64/0x310 [mt7921_common]\n   mt7921_rx_check+0x5f/0xf0 [mt7921_common]\n   mt76u_rx_worker+0x1b9/0x620 [mt76_usb]\n\nDrop the event on non-mmio buses via mt76_is_mmio(), as in\ncommit 5683e1488aa9 (\"wifi: mt76: connac: do not check WED status for\nnon-mmio devices\")."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"48fab5bbef4092d925ab3214773ad12e68807223","status":"affected","lessThan":"7003a2cbddd7917933c1f169c7874cfa6ab852c3","versionType":"git"},{"version":"48fab5bbef4092d925ab3214773ad12e68807223","status":"affected","lessThan":"ef2ee5f820c3ef87643b51e960c20b4a14d8336b","versionType":"git"},{"version":"48fab5bbef4092d925ab3214773ad12e68807223","status":"affected","lessThan":"ecf995b828191829ba4a87169bccabcbeb5c9c32","versionType":"git"},{"version":"48fab5bbef4092d925ab3214773ad12e68807223","status":"affected","lessThan":"263816e92e8d66c81c98ccab2b5d2191ed08ec71","versionType":"git"},{"version":"48fab5bbef4092d925ab3214773ad12e68807223","status":"affected","lessThan":"24475d2ddc8d8dfd82f4d2be0d951401f86911a6","versionType":"git"},{"version":"48fab5bbef4092d925ab3214773ad12e68807223","status":"affected","lessThan":"da4082e91acabc1498611ed8ccc53f0610baefc6","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/net/wireless/mediatek/mt76/mt7921/mac.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.16","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.16","versionType":"semver"},{"version":"6.1.183","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.148","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.101","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.42","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.6","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/net/wireless/mediatek/mt76/mt7921/mac.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/7003a2cbddd7917933c1f169c7874cfa6ab852c3"},{"url":"https://git.kernel.org/stable/c/ef2ee5f820c3ef87643b51e960c20b4a14d8336b"},{"url":"https://git.kernel.org/stable/c/ecf995b828191829ba4a87169bccabcbeb5c9c32"},{"url":"https://git.kernel.org/stable/c/263816e92e8d66c81c98ccab2b5d2191ed08ec71"},{"url":"https://git.kernel.org/stable/c/24475d2ddc8d8dfd82f4d2be0d951401f86911a6"},{"url":"https://git.kernel.org/stable/c/da4082e91acabc1498611ed8ccc53f0610baefc6"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-08-19T16:31:09.017Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.16","versionEndExcluding":"6.1.183"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.16","versionEndExcluding":"6.6.148"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.16","versionEndExcluding":"6.12.101"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.16","versionEndExcluding":"6.18.42"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.16","versionEndExcluding":"7.1.6"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.16","versionEndExcluding":"7.2"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}