Vulnerability in Linux Kernel
CVE-2021-4037
A vulnerability was found in the fs/inode.c:inode_init_owner() function logic of the LInux kernel that allows local users to create files for the XFS file-system with an unintended group ownership and with group execution and SGID permission bits set, in a scenario where a directory is SGID and belongs to a certain group and is writable by a user who is not a member of this group. This can lead to excessive permissions granted in case when they should not. This vulnerability is similar to the previous CVE-2018-13405 and adds the missed fix for the XFS.
EPSS: 0.003 (19.9th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 4.4 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N.
Affected products
- Linux Kernel — versions 5.5, 5.12
- Linux Linux_kernel
- Debian Debian_linux — versions 10.0, 11.0
- Red Hat Enterprise Linux 6
- Red Hat Enterprise Linux 7
- Red Hat Enterprise Linux 8 — versions 0:4.18.0-372.9.1.rt7.166.el8, 0:4.18.0-372.9.1.el8
- Red Hat Enterprise Linux 8.4 Extended Update Support — versions 0:4.18.0-305.49.1.rt7.121.el8_4, 0:4.18.0-305.49.1.el8_4
- Red Hat Enterprise Linux 9
- N/a Kernel — versions Fixed in Linux-kernel v5.11-rc1
Weakness classification (CWE)
Public proof-of-concept exploits
References
- af854a3a-2127-422b-91ae-364da2661108 (Permissions Required, Third Party Advisory, Issue Tracking)
- secalert@redhat.com (x_refsource_REDHAT, issue-tracking, Third Party Advisory, Issue Tracking)
- secalert@redhat.com (x_refsource_REDHAT, Third Party Advisory, vdb-entry)
- secalert@redhat.com (Patch, Mailing List, Vendor Advisory)
- secalert@redhat.com (Patch, Mailing List, Vendor Advisory)
- af854a3a-2127-422b-91ae-364da2661108 (vendor-advisory, Third Party Advisory)
- af854a3a-2127-422b-91ae-364da2661108 (mailing-list, Mailing List, Third Party Advisory)
- secalert@redhat.com (x_refsource_REDHAT, vendor-advisory)
- secalert@redhat.com (x_refsource_REDHAT, vendor-advisory)
- secalert@redhat.com (x_refsource_REDHAT, vendor-advisory)
Frequently asked questions
- What is CVE-2021-4037?
- CVE-2021-4037 is a medium-severity vulnerability in Linux Kernel, classified under Improper Access Control. CVSS score: 4.4/10. Published 2022-08-24.
- How severe is CVE-2021-4037?
- Medium severity. CVSS v3 base score is 4.4 out of 10.
- Is CVE-2021-4037 known to be exploited?
- 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.