CVE-2021-47479: In the Linux kernel, the following vulnerability has been resolved: staging: rtl8712: fix use-after-free in rtl8712_dl_fw Syzbot reported use-after-free in…

PriorityP431high7CVSS 3.1

AVLACHPRLUINSUCHIHAH

EPSS

0.23%

13.7th percentile

In the Linux kernel, the following vulnerability has been resolved: staging: rtl8712: fix use-after-free in rtl8712_dl_fw Syzbot reported use-after-free in rtl8712_dl_fw(). The problem was in race condition between r871xu_dev_remove() ->ndo_open() callback. It's easy to see from crash log, that driver accesses released firmware in ->ndo_open() callback. It may happen, since driver was releasing firmware _before_ unregistering netdev. Fix it by moving unregister_netdev() before cleaning up resources. Call Trace: ... rtl871x_open_fw drivers/staging/rtl8712/hal_init.c:83 [inline] rtl8712_dl_fw+0xd95/0xe10 drivers/staging/rtl8712/hal_init.c:170 rtl8712_hal_init drivers/staging/rtl8712/hal_init.c:330 [inline] rtl871x_hal_init+0xae/0x180 drivers/staging/rtl8712/hal_init.c:394 netdev_open+0xe6/0x6c0 drivers/staging/rtl8712/os_intfs.c:380 __dev_open+0x2bc/0x4d0 net/core/dev.c:1484 Freed by task 1306: ... release_firmware+0x1b/0x30 drivers/base/firmware_loader/main.c:1053 r871xu_dev_remove+0xcc/0x2c0 drivers/staging/rtl8712/usb_intf.c:599 usb_unbind_interface+0x1d8/0x8d0 drivers/usb/core/driver.c:458

Affected

17 ranges

Vendor	Product	Version range	Fixed in
debian	linux	< linux 5.15.3-1 (bookworm)	linux 5.15.3-1 (bookworm)
linux	linux	—	—
linux	linux	—	—
linux	linux	>= 3.2.6 < 3.3	3.3
linux	linux	>= 8c213fa59199f9673d66970d6940fa093186642f < c430094541a80575259a94ff879063ef01473506	c430094541a80575259a94ff879063ef01473506
linux	linux	>= 8c213fa59199f9673d66970d6940fa093186642f < befd23bd3b17f1a3f9c943a8580b47444c7c63ed	befd23bd3b17f1a3f9c943a8580b47444c7c63ed
linux	linux	>= 8c213fa59199f9673d66970d6940fa093186642f < a65c9afe9f2f55b7a7fb4a25ab654cd4139683a4	a65c9afe9f2f55b7a7fb4a25ab654cd4139683a4
linux	linux	>= 8c213fa59199f9673d66970d6940fa093186642f < c052cc1a069c3e575619cf64ec427eb41176ca70	c052cc1a069c3e575619cf64ec427eb41176ca70
linux	linux_kernel	—	—
linux	linux_kernel	>= 0 < 5.10.84-1	5.10.84-1
linux	linux_kernel	>= 0 < 5.15.3-1	5.15.3-1
linux	linux_kernel	>= 0 < 5.15.3-1	5.15.3-1
linux	linux_kernel	>= 0 < 5.15.3-1	5.15.3-1
linux	linux_kernel	>= 3.2.6 < 3.3	3.3
linux	linux_kernel	>= 3.3.1 < 5.10.79	5.10.79
linux	linux_kernel	>= 5.11 < 5.14.18	5.14.18
linux	linux_kernel	>= 5.15 < 5.15.2	5.15.2

CVSS provenance

nvdv3.17.0HIGHCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

osv7.0HIGH

vendor_debian7.0HIGH

vendor_redhat7.0HIGH

Stop checking back — get the weekly exploitation signal.

Every Monday: what got weaponized or added to CISA KEV in the last seven days — each CVE cross-linked to its PoC, Nuclei template, and detection rule. Free, one email a week, unsubscribe in one click.