VulnerabilityModified
CVE-2021-4001
A race condition was found in the Linux kernel's ebpf verifier between bpf_map_update_elem and bpf_map_freeze due to a missing lock in kernel/bpf/syscall.c.
MEDIUM 4.1EPSS 0.19%
Does this matter?
Lower severity and a low EPSS score (0.19%). Track it; it rarely justifies an emergency change on its own.
Description
A race condition was found in the Linux kernel's ebpf verifier between bpf_map_update_elem and bpf_map_freeze due to a missing lock in kernel/bpf/syscall.c. In this flaw, a local user with a special privilege (cap_sys_admin or cap_bpf) can modify the frozen mapped address space. This flaw affects kernel versions prior to 5.16 rc2.
- CVSS 3.1
- 4.1 MEDIUMCVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:H/A:N
- EPSS
- 0.19% probability · 8th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-367
- Affected
- linux/linux kernel
- Source
- secalert@redhat.com
References
- https://bugzilla.redhat.com/show_bug.cgi?id=2025645Issue Tracking, Patch, Third Party Advisory
- https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf.git/commit/?id=353050be4c19e102178ccc05988101887c25ae53Patch, Third Party Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=2025645Issue Tracking, Patch, Third Party Advisory
- https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf.git/commit/?id=353050be4c19e102178ccc05988101887c25ae53Patch, Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.