CVE-2023-4732 | Kernel: race between task migrating pages and another task calling exit_mmap to release those same pages getting invalid opcode bug in include/linux/swapops.h

A flaw was found in pfn_swap_entry_to_page in memory management subsystem in the Linux Kernel. In this flaw, an attacker with a local user privilege may cause a denial of service problem due to a BUG statement referencing pmd_t x.

Published: 2023-10-03 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2023-4732 is rated Low Risk (18.9/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.01%). Low composite risk—no urgent action required; patch on your normal maintenance cycle and revisit priority if CVSS or EPSS increases.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2023-4732

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2025-11-21 0.05% 0.01% -0.04%
2 2025-11-18 0.05% 0.05% +0.01%
3 2025-03-30 — 0.05% —

Full EPSS history (5 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2023-4732

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
4.7 3.1 MEDIUM
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/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:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
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:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 1.0 3.6 [email protected]
4.7 3.1 MEDIUM
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/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:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
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:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 1.0 3.6 [email protected]

Weakness enumeration for CVE-2023-4732

OS Trackers for CVE-2023-4732

vendor priority summary link
debian not yet assigned CVE-2023-4732 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-2023-4732
redhat medium — https://access.redhat.com/security/cve/CVE-2023-4732
ubuntu medium CVE-2023-4732 medium priority: Ubuntu including 124 source packages (linux, linux-allwinner, …), 1100 status rows across 9 suites (bionic, focal, jammy, lunar, mantic, noble, trusty, upstream, xenial): DNE 778, not-affected 129, ignored 122, released 71. https://ubuntu.com/security/CVE-2023-4732

Affected software / configurations for CVE-2023-4732

Vendor Product Version Raw CPE
linux linux_kernel <= 5.13.19 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
redhat codeready_linux_builder 8.0 cpe:2.3:a:redhat:codeready_linux_builder:8.0:*:*:*:*:*:*:*
redhat codeready_linux_builder_for_arm64 8.0_aarch64 cpe:2.3:a:redhat:codeready_linux_builder_for_arm64:8.0_aarch64:*:*:*:*:*:*:*
redhat codeready_linux_builder_for_power_little_endian 8.0_ppc64le cpe:2.3:a:redhat:codeready_linux_builder_for_power_little_endian:8.0_ppc64le:*:*:*:*:*:*:*
redhat enterprise_linux 8.0 cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:*
redhat enterprise_linux_for_arm_64 8.0_aarch64 cpe:2.3:o:redhat:enterprise_linux_for_arm_64:8.0_aarch64:*:*:*:*:*:*:*
redhat enterprise_linux_for_ibm_z_systems 8.0_s390x cpe:2.3:o:redhat:enterprise_linux_for_ibm_z_systems:8.0_s390x:*:*:*:*:*:*:*
redhat enterprise_linux_for_power_little_endian 8.0_ppc64le cpe:2.3:o:redhat:enterprise_linux_for_power_little_endian:8.0_ppc64le:*:*:*:*:*:*:*
redhat enterprise_linux_for_real_time 8.0 cpe:2.3:o:redhat:enterprise_linux_for_real_time:8.0:*:*:*:*:*:*:*
redhat enterprise_linux_for_real_time_for_nfv 8.0 cpe:2.3:o:redhat:enterprise_linux_for_real_time_for_nfv:8.0:*:*:*:*:*:*:*

References for CVE-2023-4732

cvelogic Threat Intelligence