CVE-2023-53376 | scsi: mpi3mr: Use number of bits to manage bitmap sizes

In the Linux kernel, the following vulnerability has been resolved: scsi: mpi3mr: Use number of bits to manage bitmap sizes To allocate bitmaps, the mpi3mr driver calculates sizes of bitmaps using byte as unit. However, bitmap helper functions assume that bitmaps are allocated using unsigned long as unit. This gap causes memory access beyond the bitmap sizes and results in "BUG: KASAN: slab-out-of-bounds". The BUG was observed at firmware download to eHBA-9600. Call trace indicated that the out-of-bounds access happened in find_first_zero_bit() called from mpi3mr_send_event_ack() for miroc->evtack_cmds_bitmap. To fix the BUG, do not use bytes to manage bitmap sizes. Instead, use number of bits, and call bitmap helper functions which take number of bits as arguments. For memory allocation, call bitmap_zalloc() instead of kzalloc() and krealloc(). For memory free, call bitmap_free() instead of kfree(). For zero clear, call bitmap_clear() instead of memset(). Remove three fields for bitmap byte sizes in struct scmd_priv which are no longer required. Replace the field dev_handle_bitmap_sz with dev_handle_bitmap_bits to keep number of bits of removepend_bitmap across resize.

Published: 2025-09-18 Last update: 2026-06-17 Assigner: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67

Conclusion & alert: CVE-2023-53376 is rated Low Risk (30/100): CVSS High severity, with low exploitation likelihood (EPSS 0.15%). Mandatory action: Monitor for updates and reassess as exploit intelligence or EPSS changes.

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-2023-53376

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 2026-06-15 0.02% 0.15% +0.13%
2 2025-09-19 0.02%

Full EPSS history (2 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2023-53376

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.1 3.1 HIGH
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/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: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: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.
1.8 5.2 [email protected]
7.1 3.1 HIGH
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/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: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: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.
1.8 5.2 134c704f-9b21-4f2e-91b3-4a467353bcc0

Weakness enumeration for CVE-2023-53376

OS Trackers for CVE-2023-53376

vendor priority summary link
debian unimportant CVE-2023-53376 unimportant 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-2023-53376
redhat medium https://access.redhat.com/security/cve/CVE-2023-53376
suse medium CVE-2023-53376 severity moderate: SUSE including 74 source package names (bpftool-4.18.0-513.5.1.el8_9, bpftool-7.2.0-362.8.1.el9_3, …), 248 product×package rows across 40 product lines (SLES-LTSS-TERADATA 15 SP2, SUSE Liberty Linux 8, … (40 product lines)): Known Not Affected 199, Fixed 49. https://www.suse.com/security/cve/CVE-2023-53376/
ubuntu medium CVE-2023-53376 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 158, not-affected 118, released 88, needed 33. https://ubuntu.com/security/CVE-2023-53376

Affected software / configurations for CVE-2023-53376

Vendor Product Version Raw CPE
linux linux_kernel >= 5.14, < 6.1.18 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 6.2, < 6.2.5 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*

References for CVE-2023-53376

cvelogic Threat Intelligence