{ "schema_version": "1.6.1", "id": "RPI-CVE-2026-74409", "modified": "2026-10-09T11:39:44Z", "upstream": [ "CVE-2026-74409" ], "published": "2026-08-15T06:04:33Z", "summary": "wifi: rtw89: add bounds check on firmware mac_id in link lookup", "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nwifi: rtw89: add bounds check on firmware mac_id in link lookup\n\nThe mac_id field in RX descriptors is 8 bits wide (0-255), but\nassoc_link_on_macid[] has only RTW89_MAX_MAC_ID_NUM (128) entries.\nWhile the driver currently assigns mac_id values below 128, the\ndescriptor value comes from firmware and is not validated before use\nas an array index. Add a defensive bounds check in\nrtw89_assoc_link_rcu_dereference() to guard against out-of-range\nfirmware values.", "severity": [ { "type": "CVSS_V3", "score": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H" } ], "affected": [ { "package": { "ecosystem": "Raspberry Pi OS:13", "name": "linux" }, "versions": [ "1:6.18.29-1+rpt1", "1:6.18.33-1+rpt1", "1:6.18.34-1+rpt1", "1:6.18.39-1+rpt1" ], "ecosystem_specific": { "binaries": [ { "binary_name": "linux-image-6.18.29+rpt-rpi-2712", "binary_version": "1:6.18.29-1+rpt1" }, { "binary_name": "linux-image-6.18.29+rpt-rpi-v6", "binary_version": "1:6.18.29-1+rpt1" }, { "binary_name": "linux-image-6.18.29+rpt-rpi-v7", "binary_version": "1:6.18.29-1+rpt1" }, { "binary_name": "linux-image-6.18.29+rpt-rpi-v8", "binary_version": "1:6.18.29-1+rpt1" }, { "binary_name": "linux-image-6.18.29+rpt-rpi-v8-rt", "binary_version": "1:6.18.29-1+rpt1" }, { "binary_name": "linux-image-6.18.33+rpt-rpi-2712", "binary_version": "1:6.18.33-1+rpt1" }, { "binary_name": "linux-image-6.18.33+rpt-rpi-v6", "binary_version": "1:6.18.33-1+rpt1" }, { "binary_name": "linux-image-6.18.33+rpt-rpi-v7", "binary_version": "1:6.18.33-1+rpt1" }, { "binary_name": "linux-image-6.18.33+rpt-rpi-v8", "binary_version": "1:6.18.33-1+rpt1" }, { "binary_name": "linux-image-6.18.33+rpt-rpi-v8-rt", "binary_version": "1:6.18.33-1+rpt1" }, { "binary_name": "linux-image-6.18.34+rpt-rpi-2712", "binary_version": "1:6.18.34-1+rpt1" }, { "binary_name": "linux-image-6.18.34+rpt-rpi-v6", "binary_version": "1:6.18.34-1+rpt1" }, { "binary_name": "linux-image-6.18.34+rpt-rpi-v7", "binary_version": "1:6.18.34-1+rpt1" }, { "binary_name": "linux-image-6.18.34+rpt-rpi-v8", "binary_version": "1:6.18.34-1+rpt1" }, { "binary_name": "linux-image-6.18.34+rpt-rpi-v8-rt", "binary_version": "1:6.18.34-1+rpt1" }, { "binary_name": "linux-image-6.18.39+rpt-rpi-2712", "binary_version": "1:6.18.39-1+rpt1" }, { "binary_name": "linux-image-6.18.39+rpt-rpi-v6", "binary_version": "1:6.18.39-1+rpt1" }, { "binary_name": "linux-image-6.18.39+rpt-rpi-v7", "binary_version": "1:6.18.39-1+rpt1" }, { "binary_name": "linux-image-6.18.39+rpt-rpi-v8", "binary_version": "1:6.18.39-1+rpt1" }, { "binary_name": "linux-image-6.18.39+rpt-rpi-v8-rt", "binary_version": "1:6.18.39-1+rpt1" } ] }, "database_specific": { "per_version": { "1:6.18.29-1+rpt1": { "linux_commit": "66318c5b5cd8145a662303af12ed39ac07eb27cc", "upstream_version": "6.18.29", "assessment": "commit ancestry (strak rule)", "upstream_fixed": "6.18.40" }, "1:6.18.33-1+rpt1": { "linux_commit": "95b85bebbedcaedfa7ca79116ed38b7376fba412", "upstream_version": "6.18.33", "assessment": "commit ancestry (strak rule)", "upstream_fixed": "6.18.40" }, "1:6.18.34-1+rpt1": { "linux_commit": "c8c7494100e99ee05b11aaa4f0588a223a63d1af", "upstream_version": "6.18.34", "assessment": "commit ancestry (strak rule)", "upstream_fixed": "6.18.40" }, "1:6.18.39-1+rpt1": { "linux_commit": "60ea684a8ace97bb0db1a16e20753bdd6ab371ff", "upstream_version": "6.18.39", "assessment": "commit ancestry (strak rule)", "upstream_fixed": "6.18.40" } } } } ], "references": [ { "type": "ADVISORY", "url": "https://www.cve.org/CVERecord?id=CVE-2026-74409" }, { "type": "FIX", "url": "https://git.kernel.org/stable/c/ad445de67359f24088d4305c05fbd7e34c4e35e3" }, { "type": "FIX", "url": "https://git.kernel.org/stable/c/920101305e7601a33b9e01019f4ca526af2526ae" }, { "type": "FIX", "url": "https://git.kernel.org/stable/c/6d88244bb129755acca696f9227200f4a2d106a6" } ], "database_specific": { "source": "https://git.kernel.org/pub/scm/linux/security/vulns.git", "upstream_modified": "2026-08-17T05:50:24Z", "severity": { "source": "kernel CNA", "cvss_v3_score": 8.8, "cvss_v3_severity": "High", "scenario": "AV:A - The bug is reached when rtw89 processes WiFi RX descriptors or firmware C2H events whose mac_id is taken from device firmware after over-the-air frame reception; per kernel CNA guidance, WiFi driver bugs exploitable via injected/received 802.11 frames are Adjacent, not local or physical.\nAC:L - An adjacent attacker can repeatedly send 802.11 frames (client or softAP role) to drive normal PCI/USB RX and firmware notification paths; no rare victim state, secret, or uncontrollable memory layout is required beyond having WiFi active on an affected rtw89 device.\nPR:N - Exploitation requires only radio-range WiFi access to a victim using the rtw89 driver; the attacker needs no local shell account, kernel capability, or init-namespace root on the target system.\nUI:N - No victim interaction is required at exploitation time; once the interface is operating, malicious over-the-air traffic alone can populate firmware RX/C2H metadata with an out-of-range mac_id and hit the vulnerable lookup.\nS:U - Impact is confined to kernel/driver memory corruption and crashes on the host running rtw89; it does not cross a VM, container, or IOMMU security boundary into another authority.\nC:H - Using an unvalidated firmware mac_id (up to 255, or wider in C2H) as an index performs an out-of-bounds read of assoc_link_on_macid[], interpreting adjacent rtw89_dev fields as a station pointer and enabling further unintended kernel memory reads.\nI:H - The out-of-bounds pointer is dereferenced and used for writes and callbacks (e.g., tid_rx_stats updates, PS flag changes, ieee80211_sta_ps_transition/uapsd), giving memory corruption primitives that could be developed into arbitrary kernel write or code execution.\nA:H - Dereferencing attacker-influenced out-of-bounds pointers from assoc_link_on_macid[] can immediately trigger kernel oops/panic or hang during RX processing on production WiFi clients, softAPs, and hotspots using affected Realtek rtw89 hardware." } } }