CVE-2021-4037Kernel: security regression for cve-2018-13405
- 4.4MediumCVSS base score
- 0.34%Exploitation in 30 daysEPSS · top 72% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
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.
Timeline
ID reserved
By redhat
- 9 months later
· 9 months later
Published
- 4 years later
· 4 years later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| redhatCNA (assigner) | 3.1 | Medium4.4 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N |
| NVDNVD · Modified | 3.1 | Medium4.4 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N |
- EPSS (exploitation in 30 days)
- 0.34% · top 72% of all CVEs (14 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 4.4.
Affected products
- affected < 5.4.241
- affected 5.5 – < 5.10.146
- unaffected 5.12
Red Hat · Red Hat Enterprise Linux 8
- unaffected 0:4.18.0-372.9.1.rt7.166.el8 – < *
Red Hat · Red Hat Enterprise Linux 8
- unaffected 0:4.18.0-372.9.1.el8 – < *
Red Hat · Red Hat Enterprise Linux 8.4 Extended Update Support
- unaffected 0:4.18.0-305.49.1.rt7.121.el8_4 – < *
Red Hat · Red Hat Enterprise Linux 8.4 Extended Update Support
- unaffected 0:4.18.0-305.49.1.el8_4 – < *
Red Hat · Red Hat Enterprise Linux 6
All versions: unaffected
Red Hat · Red Hat Enterprise Linux 7
All versions: unaffected
Red Hat · Red Hat Enterprise Linux 7
All versions: unaffected
Red Hat · Red Hat Enterprise Linux 9
All versions: unaffected
What to do
Workaround: Mitigation for this issue is either not available or the currently available options don't meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
References
References13
- RHSA-2022:1975 (opens in a new tab)vendor-advisoryx_refsource_REDHAT
- RHSA-2022:1988 (opens in a new tab)vendor-advisoryx_refsource_REDHAT
- RHSA-2022:4829 (opens in a new tab)vendor-advisoryx_refsource_REDHAT
- RHSA-2022:4835 (opens in a new tab)vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/security/cve/CVE-2021-4037 (opens in a new tab)vdb-entryx_refsource_REDHATx_transferred
- RHBZ#2027239 (opens in a new tab)issue-trackingx_refsource_REDHATx_transferred
- https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=01ea173e103e (opens in a new tab)x_transferred
- https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=0fa3ecd87848 (opens in a new tab)x_transferred
- https://bugzilla.redhat.com/show_bug.cgi?id=2004810 (opens in a new tab)x_transferred
- DSA-5257 (opens in a new tab)vendor-advisoryx_transferred
- [debian-lts-announce] 20221101 [SECURITY] [DLA 3173-1] linux-5.10 security update (opens in a new tab)mailing-listx_transferred
- https://cert-portal.siemens.com/productcert/html/ssa-794697.html (opens in a new tab)
- https://cert-portal.siemens.com/productcert/html/ssa-806742.html (opens in a new tab)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2021-33937 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2021-4037)Record last updated .