CVE-2023-53086: Vulnerability in Linux Linux

Severity: mediumType: vulnerabilityCVE-2023-53086

In the Linux kernel, the following vulnerability has been resolved: wifi: mt76: connac: do not check WED status for non-mmio devices WED is supported just for mmio devices, so do not check it for usb or sdio devices. This patch fixes the crash reported below: [ 21.946627] wlp0s3u1i3: authenticate with c4:41:1e:f5:2b:1d [ 22.525298] wlp0s3u1i3: send auth to c4:41:1e:f5:2b:1d (try 1/3) [ 22.548274] wlp0s3u1i3: authenticate with c4:41:1e:f5:2b:1d [ 22.557694] wlp0s3u1i3: send auth to c4:41:1e:f5:2b:1d (try 1/3) [ 22.565885] wlp0s3u1i3: authenticated [ 22.569502] wlp0s3u1i3: associate with c4:41:1e:f5:2b:1d (try 1/3) [ 22.578966] wlp0s3u1i3: RX AssocResp from c4:41:1e:f5:2b:1d (capab=0x11 status=30 aid=3) [ 22.579113] wlp0s3u1i3: c4:41:1e:f5:2b:1d rejected association temporarily; comeback duration 1000 TU (1024 ms) [ 23.649518] wlp0s3u1i3: associate with c4:41:1e:f5:2b:1d (try 2/3) [ 23.752528] wlp0s3u1i3: RX AssocResp from c4:41:1e:f5:2b:1d (capab=0x11 status=0 aid=3) [ 23.797450] wlp0s3u1i3: associated [ 24.959527] kernel tried to execute NX-protected page - exploit attempt? (uid: 0) [ 24.959640] BUG: unable to handle page fault for address: ffff88800c223200 [ 24.959706] #PF: supervisor instruction fetch in kernel mode [ 24.959788] #PF: error_code(0x0011) - permissions violation [ 24.959846] PGD 2c01067 P4D 2c01067 PUD 2c02067 PMD c2a8063 PTE 800000000c223163 [ 24.959957] Oops: 0011 [#1] PREEMPT SMP [ 24.960009] CPU: 0 PID: 391 Comm: wpa_supplicant Not tainted 6.2.0-kvm #18 [ 24.960089] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.1-2.fc37 04/01/2014 [ 24.960191] RIP: 0010:0xffff88800c223200 [ 24.960446] RSP: 0018:ffffc90000ff7698 EFLAGS: 00010282 [ 24.960513] RAX: ffff888028397010 RBX: ffff88800c26e630 RCX: 0000000000000058 [ 24.960598] RDX: ffff88800c26f844 RSI: 0000000000000006 RDI: ffff888028397010 [ 24.960682] RBP: ffff88800ea72f00 R08: 18b873fbab2b964c R09: be06b38235f3c63c [ 24.960766] R10: 18b873fbab2b964c R11: be06b38235f3c63c R12: 0000000000000001 [ 24.960853] R13: ffff88800c26f84c R14: ffff8880063f0ff8 R15: ffff88800c26e644 [ 24.960950] FS: 00007effcea327c0(0000) GS:ffff88807dc00000(0000) knlGS:0000000000000000 [ 24.961036] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 24.961106] CR2: ffff88800c223200 CR3: 000000000eaa2000 CR4: 00000000000006b0 [ 24.961190] Call Trace: [ 24.961219] <TASK> [ 24.961245] ? mt76_connac_mcu_add_key+0x2cf/0x310 [ 24.961313] ? mt7921_set_key+0x150/0x200 [ 24.961365] ? drv_set_key+0xa9/0x1b0 [ 24.961418] ? ieee80211_key_enable_hw_accel+0xd9/0x240 [ 24.961485] ? ieee80211_key_replace+0x3f3/0x730 [ 24.961541] ? crypto_shash_setkey+0x89/0xd0 [ 24.961597] ? ieee80211_key_link+0x2d7/0x3a0 [ 24.961664] ? crypto_aead_setauthsize+0x31/0x50 [ 24.961730] ? sta_info_hash_lookup+0xa6/0xf0 [ 24.961785] ? ieee80211_add_key+0x1fc/0x250 [ 24.961842] ? rdev_add_key+0x41/0x140 [ 24.961882] ? nl80211_parse_key+0x6c/0x2f0 [ 24.961940] ? nl80211_new_key+0x24a/0x290 [ 24.961984] ? genl_rcv_msg+0x36c/0x3a0 [ 24.962036] ? rdev_mod_link_station+0xe0/0xe0 [ 24.962102] ? nl80211_set_key+0x410/0x410 [ 24.962143] ? nl80211_pre_doit+0x200/0x200 [ 24.962187] ? genl_bind+0xc0/0xc0 [ 24.962217] ? netlink_rcv_skb+0xaa/0xd0 [ 24.962259] ? genl_rcv+0x24/0x40 [ 24.962300] ? netlink_unicast+0x224/0x2f0 [ 24.962345] ? netlink_sendmsg+0x30b/0x3d0 [ 24.962388] ? ____sys_sendmsg+0x109/0x1b0 [ 24.962388] ? ____sys_sendmsg+0x109/0x1b0 [ 24.962440] ? __import_iovec+0x2e/0x110 [ 24.962482] ? ___sys_sendmsg+0xbe/0xe0 [ 24.962525] ? mod_objcg_state+0x25c/0x330 [ 24.962576] ? __dentry_kill+0x19e/0x1d0 [ 24.962618] ? call_rcu+0x18f/0x270 [ 24.962660] ? __dentry_kill+0x19e/0x1d0 [ 24.962702] ? __x64_sys_sendmsg+0x70/0x90 [ 24.962744] ? do_syscall_64+0x3d/0x80 [ 24.962796] ? exit_to_user_mode_prepare+0x1b/0x70 [ 24.962852] ? entry_SYSCA ---truncated---

AI Analysis

Technical Summary

CVE-2023-53086 is a vulnerability identified in the Linux kernel's wireless driver subsystem, specifically within the mt76 driver for MediaTek Connac Wi-Fi devices. The issue arises from improper handling of the Wireless Ethernet Device (WED) status check, which is only supported for memory-mapped I/O (mmio) devices but was erroneously applied to non-mmio devices such as USB or SDIO interfaces. This incorrect check leads to a kernel crash, as demonstrated by the kernel panic and page fault logs indicating an attempt to execute a non-executable (NX-protected) page in kernel mode. The crash is triggered during Wi-Fi authentication and association processes, particularly when adding encryption keys via the mt76_connac_mcu_add_key function. The vulnerability causes a denial of service (DoS) condition by crashing the kernel, potentially impacting system stability and availability. The patch fixes this by ensuring the WED status check is only performed on supported mmio devices, preventing the crash on unsupported device types. There is no evidence of privilege escalation or remote code execution exploitation in the disclosed information, and no known exploits are reported in the wild. The vulnerability affects specific Linux kernel versions identified by commit hashes, and it is relevant to systems using affected MediaTek Wi-Fi chipsets with the mt76 driver.

Potential Impact

For European organizations, this vulnerability primarily poses a risk of denial of service on Linux-based systems utilizing affected MediaTek Wi-Fi hardware with the mt76 driver. Such systems could experience unexpected kernel crashes during normal Wi-Fi operations, leading to service interruptions, potential data loss, and reduced system availability. This is particularly critical for enterprises relying on Linux servers, embedded devices, or network infrastructure that use these Wi-Fi chipsets for connectivity. The impact is more pronounced in environments where uptime and network reliability are essential, such as telecommunications, industrial control systems, and critical infrastructure. However, since there is no indication of remote code execution or privilege escalation, the confidentiality and integrity of data are less likely to be directly compromised by this vulnerability. The lack of known exploits reduces immediate threat levels, but unpatched systems remain vulnerable to accidental or targeted DoS conditions.

Mitigation Recommendations

To mitigate this vulnerability, European organizations should: 1) Apply the official Linux kernel patches that correct the WED status check logic in the mt76 driver as soon as they become available from trusted Linux distributions or kernel maintainers. 2) Identify and inventory systems running affected Linux kernel versions with MediaTek mt76 Wi-Fi drivers, focusing on devices using USB or SDIO interfaces for Wi-Fi connectivity. 3) Where patching is not immediately feasible, consider disabling or replacing affected Wi-Fi hardware with alternatives not impacted by this issue to maintain system stability. 4) Implement monitoring for kernel crashes and system reboots related to Wi-Fi operations to detect potential exploitation or accidental triggers. 5) Coordinate with hardware vendors and Linux distribution providers to ensure timely updates and support. 6) For critical systems, consider network segmentation and redundancy to minimize the impact of potential DoS conditions caused by this vulnerability.