TI-2021-21590 Aliases CVE-2021-46923 GHSA-f93f-4q67-pcmr

fs/mount_setattr: always cleanup mount_kattr

LOW 24CWE-668Published 2024-02-27 · Updated 2026-05-11

Key facts

Attack vector: Local
Privileges required: Low
User interaction: None
Attack complexity: Low
Impact type: Information disclosure
Confidentiality · integrity · availability: High · None · None
Fix status: Partial Red Hat: 3 without a fix

Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat. Impact type from CWE-668 and the CVSS impact.

Summary

In the Linux kernel, the following vulnerability has been resolved: fs/mount_setattr: always cleanup mount_kattr Make sure that finish_mount_kattr() is called after mount_kattr was succesfully built in both the success and failure case to prevent leaking any references we took when we built it. We returned early if path lookup failed thereby risking to leak an additional reference we took when building mount_kattr when an idmapped mount was requested.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV

EPSS 0.00211 11th percentileScored 2026-11-07

Fix Partial Linux (Linux): 5.15.13, 5.16Red Hat: 3 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: None
Automatable: No
Technical impact: Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
Linux	Linux	5.12 and later	5.15.13, 5.16	Patch available	CNA

Linux VendorLinux Affected 5.12 and later Fixed in 5.15.13, 5.16 Patch available CNA

CPE configurations NVD · 1

CPE	Versions	Role	Vendor
cpe:2.3:o:linux:linux_kernel::::::::	5.12.0 to before 5.15.13	Vulnerable	Linux

cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions 5.12.0 to before 5.15.13 Vulnerable ·Linux

Remediation

Fix · CNA Linux (Linux) Fixed in 5.15.13, 5.16

Vendor assessments

Red Hat

Red Hat rating: Low. Red Hat's page for this CVE →

Product	Status	Plan or fix
Red Hat Enterprise Linux 6	Affected	No fix planned: Out of support scope
Red Hat Enterprise Linux 7	Affected	No fix planned: Out of support scope
Red Hat Enterprise Linux 9	Affected	No fix yet

Not affected: 2 products

Red Hat Enterprise Linux 8
Red Hat Enterprise Linux 9

Timeline

2026-10-02 Threatist record created from CVE-2021-46923
2026-10-03 Alias added: GHSA-f93f-4q67-pcmr

References

Patch 2

TI-2025-26358 tls: fix handling of zero-length records on the rx_list KEVCVSS 3.1CRITICAL 9.8
TI-2026-38352 netfilter: bridge: make ebt_snat ARP rewrite writable KEVCVSS 3.1HIGH 8.8
TI-2013-05264 The (1) get_user and (2) put_user API functions in the Linux kernel before 3.5.5 on the… KEVCVSS 3.1HIGH 8.8
TI-2022-00125 Integer overflow in kernel KEVCVSS 3.1HIGH 8.4
TI-2013-01864 The perf_swevent_init function in kernel/events/core.c in the Linux kernel before 3.8.9… KEVCVSS 3.1HIGH 8.4
TI-2021-05514 Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACE KEVCVSS 3.1HIGH 8.3

See all 15278 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences