CVSS3
Attack Vector
LOCAL
Attack Complexity
LOW
Privileges Required
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
HIGH
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
AI Score
Confidence
Low
EPSS
Percentile
5.1%
In the Linux kernel, the following vulnerability has been resolved: mt76:
mt7915: fix NULL pointer dereference in mt7915_get_phy_mode Fix the
following NULL pointer dereference in mt7915_get_phy_mode routine adding an
ibss interface to the mt7915 driver. [ 101.137097] wlan0: Trigger new scan
to find an IBSS to join [ 102.827039] wlan0: Creating new IBSS network,
BSSID 26:a4:50:1a:6e:69 [ 103.064756] Unable to handle kernel NULL pointer
dereference at virtual address 0000000000000000 [ 103.073670] Mem abort
info: [ 103.076520] ESR = 0x96000005 [ 103.079614] EC = 0x25: DABT (current
EL), IL = 32 bits [ 103.084934] SET = 0, FnV = 0 [ 103.088042] EA = 0,
S1PTW = 0 [ 103.091215] Data abort info: [ 103.094104] ISV = 0, ISS =
0x00000005 [ 103.098041] CM = 0, WnR = 0 [ 103.101044] user pgtable: 4k
pages, 39-bit VAs, pgdp=00000000460b1000 [ 103.107565] [0000000000000000]
pgd=0000000000000000, p4d=0000000000000000, pud=0000000000000000 [
103.116590] Internal error: Oops: 96000005 [#1] SMP [ 103.189066] CPU: 1
PID: 333 Comm: kworker/u4:3 Not tainted 5.10.75 #0 [ 103.195498] Hardware
name: MediaTek MT7622 RFB1 board (DT) [ 103.201124] Workqueue: phy0
ieee80211_iface_work [mac80211] [ 103.206695] pstate: 20000005 (nzCv daif
-PAN -UAO -TCO BTYPE=–) [ 103.212705] pc : mt7915_get_phy_mode+0x68/0x120
[mt7915e] [ 103.218103] lr : mt7915_mcu_add_bss_info+0x11c/0x760 [mt7915e]
[ 103.223927] sp : ffffffc011cdb9e0 [ 103.227235] x29: ffffffc011cdb9e0
x28: ffffff8006563098 [ 103.232545] x27: ffffff8005f4da22 x26:
ffffff800685ac40 [ 103.237855] x25: 0000000000000001 x24: 000000000000011f
[ 103.243165] x23: ffffff8005f4e260 x22: ffffff8006567918 [ 103.248475]
x21: ffffff8005f4df80 x20: ffffff800685ac58 [ 103.253785] x19:
ffffff8006744400 x18: 0000000000000000 [ 103.259094] x17: 0000000000000000
x16: 0000000000000001 [ 103.264403] x15: 000899c3a2d9d2e4 x14:
000899bdc3c3a1c8 [ 103.269713] x13: 0000000000000000 x12: 0000000000000000
[ 103.275024] x11: ffffffc010e30c20 x10: 0000000000000000 [ 103.280333] x9
: 0000000000000050 x8 : ffffff8006567d88 [ 103.285642] x7 :
ffffff8006563b5c x6 : ffffff8006563b44 [ 103.290952] x5 : 0000000000000002
x4 : 0000000000000001 [ 103.296262] x3 : 0000000000000001 x2 :
0000000000000001 [ 103.301572] x1 : 0000000000000000 x0 : 0000000000000011
[ 103.306882] Call trace: [ 103.309328] mt7915_get_phy_mode+0x68/0x120
[mt7915e] [ 103.314378] mt7915_bss_info_changed+0x198/0x200 [mt7915e] [
103.319941] ieee80211_bss_info_change_notify+0x128/0x290 [mac80211] [
103.326360] __ieee80211_sta_join_ibss+0x308/0x6c4 [mac80211] [ 103.332171]
ieee80211_sta_create_ibss+0x8c/0x10c [mac80211] [ 103.337895]
ieee80211_ibss_work+0x3dc/0x614 [mac80211] [ 103.343185]
ieee80211_iface_work+0x388/0x3f0 [mac80211] [ 103.348495]
process_one_work+0x288/0x690 [ 103.352499] worker_thread+0x70/0x464 [
103.356157] kthread+0x144/0x150 [ 103.359380] ret_from_fork+0x10/0x18 [
103.362952] Code: 394008c3 52800220 394000e4 7100007f (39400023)
git.kernel.org/linus/6e53d6d26920d5221d3f4d4f5ffdd629ea69aa5c (5.16-rc4)
git.kernel.org/stable/c/14b03b8cebdf18ff13c39d58501b625411314de2
git.kernel.org/stable/c/6e53d6d26920d5221d3f4d4f5ffdd629ea69aa5c
git.kernel.org/stable/c/932b338f4e5c4cb0c2ed640da3bced1e63620198
launchpad.net/bugs/cve/CVE-2021-47540
nvd.nist.gov/vuln/detail/CVE-2021-47540
security-tracker.debian.org/tracker/CVE-2021-47540
www.cve.org/CVERecord?id=CVE-2021-47540