CVSS 3.1
4.4 mediumCVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:NCVE-2021-4159
Medium (4.4). EPSS 0.2% chance of exploitation in the next 30 days.
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.
Severity
- EPSS
- 0.2% chance of exploitation in the next 30 days; higher than 16% of CVEs (scores of 2026-10-31)
- CWE
- CWE-202
- Published
- Modified
- Record from
- the NVD, synced
Affected
- debian:debian_linux
- linux:linux_kernel
- redhat:enterprise_linux
References
- https://access.redhat.com/security/cve/CVE-2021-4159
- https://bugzilla.redhat.com/show_bug.cgi?id=2036024
- https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=294f2fc6da27620a506e6c050241655459ccd6bd
- https://lists.debian.org/debian-lts-announce/2022/10/msg00000.html
- https://security-tracker.debian.org/tracker/CVE-2021-4159