TI-2023-30385 Aliases CVE-2023-54107 GHSA-4mrm-9mrj-crwx

blk-cgroup: dropping parent refcount after pd_free_fn() is done

LOW 35Published 2025-12-24 · Updated 2026-10-30

Key facts

Attack vector: Local
Privileges required: Low
User interaction: None
Attack complexity: Low
Impact type: —
Confidentiality · integrity · availability: High · High · High
Fix status: Partial Red Hat: 4 without a fix

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat.

Summary

In the Linux kernel, the following vulnerability has been resolved: blk-cgroup: dropping parent refcount after pd_free_fn() is done Some cgroup policies will access parent pd through child pd even after pd_offline_fn() is done. If pd_free_fn() for parent is called before child, then UAF can be triggered. Hence it's better to guarantee the order of pd_free_fn(). Currently refcount of parent blkg is dropped in __blkg_release(), which is before pd_free_fn() is called in blkg_free_work_fn() while blkg_free_work_fn() is called asynchronously. This patch make sure pd_free_fn() called from removing cgroup is ordered by delaying dropping parent refcount after calling pd_free_fn() for child. BTW, pd_free_fn() will also be called from blkcg_deactivate_policy() from deleting device, and following patches will guarantee the order.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV

EPSS 0.00155 4th percentileScored 2026-11-07

Fix Partial Linux (Linux): 6.1.191, 6.3Red Hat: 4 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: None
Automatable: No
Technical impact: Total

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	5.18 and later	6.1.191, 6.3	Patch available	CNA

Linux VendorLinux Affected 5.18 and later Fixed in 6.1.191, 6.3 Patch available CNA

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPE	Versions	Role	Vendor
cpe:2.3:o:linux:linux_kernel::::::::	—	—	Linux

cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions — — ·Linux

Remediation

Fix · CNA Linux (Linux) Fixed in 6.1.191, 6.3

Vendor assessments

Red Hat

Red Hat rating: Moderate. 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 yet: Fix deferred
Red Hat Enterprise Linux 8	Affected	No fix yet: Fix deferred
Red Hat Enterprise Linux 9	Affected	No fix yet: Fix deferred

Not affected: 1 product

Red Hat Enterprise Linux 10

Timeline

2026-10-02 Threatist record created from CVE-2023-54107
2026-10-03 Alias added: GHSA-4mrm-9mrj-crwx
2026-10-16 CISA SSVC decision points changed
2026-10-30 Fix available: Linux/[email protected], Linux/Linux@c2f355e68126fd374e3bc0782aa6840faa7d3b1f · CNA
2026-10-30 1 new reference · CNA

References

Other 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-2021-02452 Incorrect authorization in Ubuntu linux kernel 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

See all 21741 →

Sources

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