CVE-2024-56769 media: dvb-frontends: dib3000mb: fix uninit-value in dib3000_write_reg
An uninitialized memory read in the Linux kernel DVB frontend driver may allow local attackers to disclose sensitive kernel memory contents.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2024-56769?
CVE-2024-56769 is a medium-severity vulnerability in Linux kernel, published on 6 Jan 2025. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
media: dvb-frontends: dib3000mb: fix uninit-value in dib3000_write_reg
Syzbot reports [1] an uninitialized value issue found by KMSAN in dib3000_read_reg().
Local u8 rb[2] is used in i2c_transfer() as a read buffer; in case that call fails, the buffer may end up with some undefined values.
Since no elaborate error handling is expected in dib3000_write_reg(), simply zero out rb buffer to mitigate the problem.
[1] Syzkaller report dvb-usb: bulk message failed: -22 (6/0) ===================================================== BUG: KMSAN: uninit-value in dib3000mb_attach+0x2d8/0x3c0 drivers/media/dvb-frontends/dib3000mb.c:758 dib3000mb_attach+0x2d8/0x3c0 drivers/media/dvb-frontends/dib3000mb.c:758 dibusb_dib3000mb_frontend_attach+0x155/0x2f0 drivers/media/usb/dvb-usb/dibusb-mb.c:31 dvb_usb_adapter_frontend_init+0xed/0x9a0 drivers/media/usb/dvb-usb/dvb-usb-dvb.c:290 dvb_usb_adapter_init drivers/media/usb/dvb-usb/dvb-usb-init.c:90 [inline] dvb_usb_init drivers/media/usb/dvb-usb/dvb-usb-init.c:186 [inline] dvb_usb_device_init+0x25a8/0x3760 drivers/media/usb/dvb-usb/dvb-usb-init.c:310 dibusb_probe+0x46/0x250 drivers/media/usb/dvb-usb/dibusb-mb.c:110 ... Local variable rb created at: dib3000_read_reg+0x86/0x4e0 drivers/media/dvb-frontends/dib3000mb.c:54 dib3000mb_attach+0x123/0x3c0 drivers/media/dvb-frontends/dib3000mb.c:758 ...
Weakness: CWE-908
Which versions are affected by CVE-2024-56769?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2024-56769?
Apply the vendor's patch.
Is CVE-2024-56769 being exploited?
There is no known exploitation of CVE-2024-56769 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as AZL-55056, AZL-55082, BELL-CVE-2024-56769, DEBIAN-CVE-2024-56769, GHSA-q23h-j65c-73m4, UBUNTU-CVE-2024-56769.