CVE-2021-4159
kernel: another kernel ptr leak vulnerability via BPF in coerce_reg_to_size
Severity
ModerateRed Hat Product Security
CVSS 3.1
Review impact separately from score.
Published · January 28, 2022
Updated · November 3, 2026
Description
A vulnerability was found in the Linux kernel's EBPF verifier when handling internal data structures. Internal memory locations could be returned to userspace. A local attacker with the permissions to insert eBPF code to the kernel can use this to leak internal kernel memory details defeating some of the exploit mitigations in place for the kernel.
CVSS score applicability
The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.
Mitigation
Mitigation for this issue is either not available or the currently available options does not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
CVSS / CWE
CVSS 3.1 · 4.4CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N
CWE-497 · Exposure of Sensitive System Information to an Unauthorized Control Sphere