{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-90381", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-11T19:38:34.809Z", "datePublished": "2026-09-17T16:09:18.603Z", "dateUpdated": "2026-10-19T09:02:40.869Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-19T09:02:40.869Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nwifi: mt76: fix handling channel context with different bands in mt76_switch_vif_chanctx()\n\nWhen performing channel switches on different radios within a short\ntimeframe, channel contexts with different bands can be carried for\neach struct ieee80211_vif_chanctx_switch.\n\nRework mt76_switch_vif_chanctx() to properly handle this scenario." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "baseScore": 8.8, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:A - CSA IEs in a received Beacon (ieee80211_rx_mgmt_beacon → ieee80211_sta_process_chanswitch → ieee80211_link_reserve_chanctx) or Channel Switch action frame (ieee80211_sta_rx_queued_mgmt) make ieee80211_chsw_switch_vifs call mt76_switch_vif_chanctx with one ieee80211_vif_chanctx_switch per radio; those 802.11 frames are radio-range, not a routable IP protocol.\nAC:L - ieee80211_vif_use_reserved_switch returns -EAGAIN until every in-place reservation is reserved_ready, then ieee80211_chsw_switch_vifs batches them into one CHANCTX_SWMODE_SWAP_CONTEXTS call; an AP/MLD that puts CSA IEs on two mt7996 bands with matching counts makes both ready in order with no victim-only race.\nPR:N - ieee80211_rx_mgmt_beacon only needs ieee80211_rx_our_beacon() BSSID match on an associated STA, and mt7996 sets CHANCTX_STA_CSA so this path is used; beacons are unauthenticated, so the AP or a radio-range BSSID spoof needs no Linux capability or account.\nUI:N - An already-associated station runs ieee80211_csa_switch_work → ieee80211_link_use_reserved_context when the CSA count elapses and automatically enters mt76_switch_vif_chanctx; no extra click, reconnect, or mount is required at trigger time.\nS:U - Aliased mlink->ctx, the leftover phy->chanctx on non-first radios, and any resulting host-kernel heap UAF stay inside this machine’s mt76/mac80211; no VM, IOMMU, or sandbox boundary is crossed.\nC:H - The pre-fix function set every mlink->ctx to vifs[0].new_ctx. After that first ieee80211_chanctx is kfree_rcu’d (ieee80211_free_chanctx when the first vif/link unassigns while others remain), mt76_vif_link_phy() still does mlink->ctx->drv_priv and reads ctx->phy from the freed object, a kernel info-leak UAF.\nI:H - The same dangling mlink->ctx makes mt76_vif_link_phy() return ctx->phy from reallocatable freed ieee80211_chanctx memory; callers such as mt7996_link_info_changed then issue MCU updates (mt7996_mcu_add_bss_info and similar) through that forged mt76_phy pointer, a kernel write/control-flow primitive.\nA:H - mt76_vif_link_phy() on the stale mlink->ctx oopses after the aliased chanctx is freed; the pre-fix path also skipped mt76_phy_update_channel for every radio but vifs[0], leaving that PHY’s phy->chanctx pointing at the old ctx that ieee80211_vif_use_reserved_switch kfree_rcu’s, taking the radio down." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/net/wireless/mediatek/mt76/channel.c" ], "versions": [ { "version": "82334623af0cd2154633cdb007719a321048fafc", "lessThan": "7a1b971b799eae8a957acb90d8100576df889644", "status": "affected", "versionType": "git" }, { "version": "82334623af0cd2154633cdb007719a321048fafc", "lessThan": "063169a2755abdcbe7698d98360336abb6bef414", "status": "affected", "versionType": "git" }, { "version": "82334623af0cd2154633cdb007719a321048fafc", "lessThan": "70869cc429fffc77de51e7777c0ecb651e8fca07", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/net/wireless/mediatek/mt76/channel.c" ], "versions": [ { "version": "6.14", "status": "affected" }, { "version": "0", "lessThan": "6.14", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.57", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.2.6", "lessThanOrEqual": "7.2.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.3", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix" } ] } ], "cpeApplicability": [ { "nodes": [ { "operator": "OR", "negate": false, "cpeMatch": [ { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.14", "versionEndExcluding": "6.18.57" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.14", "versionEndExcluding": "7.2.6" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.14", "versionEndExcluding": "7.3" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/7a1b971b799eae8a957acb90d8100576df889644" }, { "url": "https://git.kernel.org/stable/c/063169a2755abdcbe7698d98360336abb6bef414" }, { "url": "https://git.kernel.org/stable/c/70869cc429fffc77de51e7777c0ecb651e8fca07" } ], "title": "wifi: mt76: fix handling channel context with different bands in mt76_switch_vif_chanctx()", "x_generator": { "engine": "bippy-1.2.0" } } } }