CVE-2023-53446 [High] | Use-After-Free in Linux Kernel

In the Linux kernel, the following vulnerability has been resolved: PCI/ASPM: Disable ASPM on MFD function removal to avoid use-after-free Struct pcie_link_state->downstream is a pointer to the pci_dev of function 0. Previously we retained that pointer when removing function 0, and subsequent ASPM policy changes dereferenced it, resulting in a use-after-free warning from KASAN, e.g.: # echo 1 > /sys/bus/pci/devices/0000:03:00.0/remove # echo powersave > /sys/module/pcie_aspm/parameters/policy BUG: KASAN: slab-use-after-free in pcie_config_aspm_link+0x42d/0x500 Call Trace: kasan_report+0xae/0xe0 pcie_config_aspm_link+0x42d/0x500 pcie_aspm_set_policy+0x8e/0x1a0 param_attr_store+0x162/0x2c0 module_attr_store+0x3e/0x80 PCIe spec r6.0, sec 7.5.3.7, recommends that software program the same ASPM Control value in all functions of multi-function devices. Disable ASPM and free the pcie_link_state when any child function is removed so we can discard the dangling pcie_link_state->downstream pointer and maintain the same ASPM Control configuration for all functions. [bhelgaas: commit log and comment]

#	Date	Old EPSS score	New EPSS score	Delta (New - Old)
1	2025-09-19	—	0.03%	—

Date

Old EPSS score

New EPSS score

Delta (New - Old)

2025-09-19

—

0.03%

—

Base score	Version	Severity	Vector	Exploitability	Impact	Score source
7.8	3.1	HIGH	`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H` Click to expand Attack vector (AV:L) They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by. Attack complexity (AC:L) Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup. Privileges required (PR:L) A normal user session is enough; they don’t have to be admin. User interaction (UI:N) Nobody has to click “OK” or open a trap file; it can work without a victim helping. Scope (S:U) Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems. Confidentiality (C:H) Serious risk that confidential data gets exposed in a big way. Integrity (I:H) They could widely tamper with or forge data—trust in the data is badly hurt. Availability (A:H) Could take the service down hard or make it unusable for people who depend on it.	1.8	5.9	[email protected]
7.8	3.1	HIGH	`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H` Click to expand Attack vector (AV:L) They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by. Attack complexity (AC:L) Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup. Privileges required (PR:L) A normal user session is enough; they don’t have to be admin. User interaction (UI:N) Nobody has to click “OK” or open a trap file; it can work without a victim helping. Scope (S:U) Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems. Confidentiality (C:H) Serious risk that confidential data gets exposed in a big way. Integrity (I:H) They could widely tamper with or forge data—trust in the data is badly hurt. Availability (A:H) Could take the service down hard or make it unusable for people who depend on it.	1.8	5.9	134c704f-9b21-4f2e-91b3-4a467353bcc0

Base score

Version

Severity

Vector

Exploitability

Impact

Score source

7.8

3.1

HIGH

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H Click to expand

Attack vector (AV:L): They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L): Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L): A normal user session is enough; they don’t have to be admin.
User interaction (UI:N): Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U): Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H): Serious risk that confidential data gets exposed in a big way.
Integrity (I:H): They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H): Could take the service down hard or make it unusable for people who depend on it.

1.8

5.9

[email protected]

7.8

3.1

HIGH

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H Click to expand

Attack vector (AV:L): They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L): Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L): A normal user session is enough; they don’t have to be admin.
User interaction (UI:N): Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U): Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H): Serious risk that confidential data gets exposed in a big way.
Integrity (I:H): They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H): Could take the service down hard or make it unusable for people who depend on it.

1.8

5.9

134c704f-9b21-4f2e-91b3-4a467353bcc0

OS Trackers for CVE-2023-53446

vendor	priority	summary	link
`debian`	not yet assigned	CVE-2023-53446 not yet assigned priority: Debian including 1 source packages (linux), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5.	https://security-tracker.debian.org/tracker/CVE-2023-53446
`redhat`	medium	—	https://access.redhat.com/security/cve/CVE-2023-53446
`suse`	medium	—	https://www.suse.com/security/cve/CVE-2023-53446/
`ubuntu`	medium	CVE-2023-53446 medium priority: Ubuntu including 158 source packages (linux, linux-allwinner-5.19, …), 1414 status rows across 9 suites (bionic, focal, jammy, noble, plucky, questing, trusty, upstream, xenial): DNE 1017, ignored 159, released 138, not-affected 84, needed 15, needs-triage 1.	https://ubuntu.com/security/CVE-2023-53446

Affected software / configurations for CVE-2023-53446

Vendor	Product	Version	Raw CPE
linux	linux_kernel	>= 4.11, < 5.4.251	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	>= 5.5, < 5.10.188	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	>= 5.11, < 5.15.121	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	>= 5.16, < 6.1.39	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	>= 6.2, < 6.3.13	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	>= 6.4, < 6.4.4	cpe:2.3:o:linux:linux_kernel::::::::

References for CVE-2023-53446

URL	Tags
https://git.kernel.org/stable/c/4203722d51afe3d239e03f15cc73efdf023a7103	Patch
https://git.kernel.org/stable/c/456d8aa37d0f56fc9e985e812496e861dcd6f2f2	Patch
https://git.kernel.org/stable/c/666e7f9d60cee23077ea3e6331f6f8a19f7ea03f	Patch
https://git.kernel.org/stable/c/7aecdd47910c51707696e8b0e045b9f88bd4230f	Patch
https://git.kernel.org/stable/c/7badf4d6f49a358a01ab072bbff88d3ee886c33b	Patch
https://git.kernel.org/stable/c/9856c0de49052174ab474113f4ba40c02aaee086	Patch
https://git.kernel.org/stable/c/d51d2eeae4ce54d542909c4d9d07bf371a78592c	Patch

URL

CVE-2023-53446 | PCI/ASPM: Disable ASPM on MFD function removal to avoid use-after-free

Exploit prediction scoring system (EPSS) score for CVE-2023-53446

Common vulnerability scoring system (CVSS) metrics for CVE-2023-53446

Weakness enumeration for CVE-2023-53446

OS Trackers for CVE-2023-53446

Affected software / configurations for CVE-2023-53446

References for CVE-2023-53446