Use After Free in Linux Kernel
CVE-2022-4696
There exists a use-after-free vulnerability in the Linux kernel through io_uring and the IORING_OP_SPLICE operation. If IORING_OP_SPLICE is missing the IO_WQ_WORK_FILES flag, which signals that the operation won't use current->nsproxy, so its reference counter is not increased. This assumption is not always true as calling io_splice on specific files will call the get_uts function which will use current->nsproxy leading to invalidly decreasing its reference counter later causing the use-after-free vulnerability. We recommend upgrading to version 5.10.160 or above
EPSS: 0.004 (36.2th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.
Affected products
Weakness classification (CWE)
Public proof-of-concept exploits
References
- cve-coordination@google.com (Exploit, Third Party Advisory)
- cve-coordination@google.com (Patch, Mailing List, Vendor Advisory)
- af854a3a-2127-422b-91ae-364da2661108 (Vendor Advisory)
Frequently asked questions
- What is CVE-2022-4696?
- CVE-2022-4696 is a high-severity vulnerability in Linux Kernel, classified under Release of Invalid Pointer or Reference. CVSS score: 7.8/10. Published 2023-01-11.
- How severe is CVE-2022-4696?
- High severity. CVSS v3 base score is 7.8 out of 10.
- Is CVE-2022-4696 known to be exploited?
- 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.