CVE-2026-43281 | mailbox: Prevent out-of-bounds access in fw_mbox_index_xlate()

In the Linux kernel, the following vulnerability has been resolved: mailbox: Prevent out-of-bounds access in fw_mbox_index_xlate() Although it is guided that `#mbox-cells` must be at least 1, there are many instances of `#mbox-cells = <0>;` in the device tree. If that is the case and the corresponding mailbox controller does not provide `fw_xlate` and of_xlate` function pointers, `fw_mbox_index_xlate()` will be used by default and out-of-bounds accesses could occur due to lack of bounds check in that function.

Published: 2026-05-06 Last update: 2026-06-01 Assigner: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-43281 is rated Low Risk (29.2/100): CVSS High severity, with low exploitation likelihood (EPSS 0.12%). 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-2026-43281

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% 0.12% +0.10%
2 2026-05-07 — 0.02% —

Full EPSS history (2 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-43281

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]

Weakness enumeration for CVE-2026-43281

GitHub Security Advisory for CVE-2026-43281

GHSA-78gq-46gf-2hpp · Severity: high — In the Linux kernel, the following vulnerability has been resolved: mailbox: Prevent out-of...

OS Trackers for CVE-2026-43281

vendor priority summary link
debian not yet assigned CVE-2026-43281 not yet assigned priority: Debian including 1 source packages (linux), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 4, open 1. https://security-tracker.debian.org/tracker/CVE-2026-43281
redhat medium — https://access.redhat.com/security/cve/CVE-2026-43281
suse medium CVE-2026-43281 severity moderate: SUSE including 4 source package names (kernel-default, kernel-default-base, kernel-default-devel, kernel-source), 4 product×package rows across 1 product lines (SUSE Linux Enterprise Server 11 SP4 LTSS EXTREME CORE): Known Not Affected 4. https://www.suse.com/security/cve/CVE-2026-43281/
ubuntu medium CVE-2026-43281 medium priority: Ubuntu including 161 source packages (linux, linux-allwinner-5.19, …), 1449 status rows across 9 suites (bionic, focal, jammy, noble, questing, resolute, trusty, upstream, xenial): DNE 1048, ignored 173, needed 130, released 83, not-affected 10, needs-triage 5. https://ubuntu.com/security/CVE-2026-43281

Affected software / configurations for CVE-2026-43281

Vendor Product Version Raw CPE
linux linux_kernel >= 3.18.1, < 6.1.167 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 6.2, < 6.6.130 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 6.7, < 6.12.77 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 6.13, < 6.18.16 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 6.19, < 6.19.6 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel 3.18 cpe:2.3:o:linux:linux_kernel:3.18:-:*:*:*:*:*:*
linux linux_kernel 3.18 cpe:2.3:o:linux:linux_kernel:3.18:rc2:*:*:*:*:*:*
linux linux_kernel 3.18 cpe:2.3:o:linux:linux_kernel:3.18:rc3:*:*:*:*:*:*
linux linux_kernel 3.18 cpe:2.3:o:linux:linux_kernel:3.18:rc4:*:*:*:*:*:*
linux linux_kernel 3.18 cpe:2.3:o:linux:linux_kernel:3.18:rc5:*:*:*:*:*:*
linux linux_kernel 3.18 cpe:2.3:o:linux:linux_kernel:3.18:rc6:*:*:*:*:*:*
linux linux_kernel 3.18 cpe:2.3:o:linux:linux_kernel:3.18:rc7:*:*:*:*:*:*

References for CVE-2026-43281

cvelogic Threat Intelligence