CVE-2022-49870 capabilities: fix undefined behavior in bit shift for CAP_TO_MASK
A signed integer overflow in Linux kernel capabilities handling can cause undefined behavior and potential system crashes.
- 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-2022-49870?
CVE-2022-49870 is a high-severity vulnerability in Linux kernel, published on 1 May 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:
capabilities: fix undefined behavior in bit shift for CAP_TO_MASK
Shifting signed 32-bit value by 31 bits is undefined, so changing significant bit to unsigned. The UBSAN warning calltrace like below:
UBSAN: shift-out-of-bounds in security/commoncap.c:1252:2 left shift of 1 by 31 places cannot be represented in type 'int' Call Trace: <TASK> dump_stack_lvl+0x7d/0xa5 dump_stack+0x15/0x1b ubsan_epilogue+0xe/0x4e __ubsan_handle_shift_out_of_bounds+0x1e7/0x20c cap_task_prctl+0x561/0x6f0 security_task_prctl+0x5a/0xb0 __x64_sys_prctl+0x61/0x8f0 do_syscall_64+0x58/0x80 entry_SYSCALL_64_after_hwframe+0x63/0xcd </TASK>
Weakness: CWE-125
Which versions are affected by CVE-2022-49870?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2022-49870?
Apply the vendor's patch.
Is CVE-2022-49870 being exploited?
There is no known exploitation of CVE-2022-49870 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as DEBIAN-CVE-2022-49870, GHSA-fw9v-j9g8-g322, UBUNTU-CVE-2022-49870.