CVE-2025-21874: linux kernel — Fix

Description

In the Linux kernel, the following vulnerability has been resolved: dm-integrity: Avoid divide by zero in table status in Inline mode In Inline mode, the journal is unused, and journal_sectors is zero. Calculating the journal watermark requires dividing by journal_sectors, which should be done only if the journal is configured. Otherwise, a simple table query (dmsetup table) can cause OOPS. This bug did not show on some systems, perhaps only due to compiler optimization. On my 32-bit testing machine, this reliably crashes with the following: : Oops: divide error: 0000 [#1] PREEMPT SMP : CPU: 0 UID: 0 PID: 2450 Comm: dmsetup Not tainted 6.14.0-rc2+ #959 : EIP: dm_integrity_status+0x2f8/0xab0 [dm_integrity] ...

Is your site exposed to CVE-2025-21874?

Run a free security scan — no signup, results in seconds.

CVSS v3.1 Score

5.5

MEDIUM

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

Weakness Type (CWE)

CWE-369 CWE-369

Affected Products

Vendor	Product	Versions
linux	linux_kernel	6.11 — 6.12.18
linux	linux_kernel	6.13 — 6.13.6
linux	linux_kernel	All
linux	linux_kernel	All
linux	linux_kernel	All
linux	linux_kernel	All

References

Advisories & Patches

https://git.kernel.org/stable/c/06d9895f265282e939a8933bb18de82eba2b4dda https://git.kernel.org/stable/c/22c6f577b3cb184857b440ae5e5916f6c9e7021d https://git.kernel.org/stable/c/7fb39882b20c98a9a393c244c86b56ef6933cff8

Frequently Asked Questions

What is CVE-2025-21874? +

In the Linux kernel, the following vulnerability has been resolved: dm-integrity: Avoid divide by zero in table status in Inline mode In Inline mode, the journal is unused, and journal_sectors is zero. Calculating the journal watermark requires dividing by journal_sectors, which should be done only if the journal is configured. Otherwise, a simple table query (dmsetup table) can cause OOPS. This bug did not show on some systems, perhaps only due to compiler optimization. On my 32-bit testing machine, this reliably crashes with the following: : Oops: divide error: 0000 [#1] PREEMPT SMP : CPU: 0 UID: 0 PID: 2450 Comm: dmsetup Not tainted 6.14.0-rc2+ #959 : EIP: dm_integrity_status+0x2f8/0xab0 [dm_integrity] ... It has a CVSS v3.1 base score of 5.5 (MEDIUM).

How severe is CVE-2025-21874? +

CVE-2025-21874 has a CVSS v3.1 score of 5.5 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

What products are affected by CVE-2025-21874? +

CVE-2025-21874 affects products from linux, specifically: linux_kernel. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2025-21874? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

Related Vulnerabilities

CVE-2025-4637

Divide By Zero vulnerability in davisking dlib allows remote attackers to cause a denial of service via a crafted file. …

CVE-2025-54873

RISC Zero is a zero-knowledge verifiable general computing platform based on zk-STARKs and the RISC-V microarchitecture. RISC packages risc0-zkvm versions …

CVE-2026-37232 8.6

An issue was discovered in OpenAirInterface5G 2.4.0 (nr-softmodem) in the E2SM-KPM RAN Function's PRB utilization metric calculation. The functions fill_RRU_PrbTotDl() …

CVE-2024-26945 8.4

In the Linux kernel, the following vulnerability has been resolved: crypto: iaa - Fix nr_cpus < nr_iaa case If nr_cpus …

CVE-2024-4785 7.6

BT: Missing Check in LL_CONNECTION_UPDATE_IND Packet Leads to Division by Zero

CVE-2024-6135 7.6

BT:Classic: Multiple missing buf length checks

CVE-2025-21874