CVE-2026-31770
MediumIn the Linux kernel, the following vulnerability has been resolved: hwmon: (occ) Fix division by zero in occ_show_power_1() In occ_show_power_1() case 1, the accumulator is divided by update_tag without checking for zero. If no samples have been collected yet (e.g. during early boot when the sensor block is included but hasn't been updated), update_tag is zero, causing a kernel divide-by-zero crash. The 2019 fix in commit 211186cae14d ("hwmon: (occ) Fix division by zero issue") only addressed occ_get_powr_avg() used by occ_show_power_2() and occ_show_power_a0(). This separate code path in occ_show_power_1() was missed. Fix this by reusing the existing occ_get_powr_avg() helper, which already handles the zero-sample case and uses mul_u64_u32_div() to multiply before dividing for better precision. Move the helper above occ_show_power_1() so it is visible at the call site. [groeck: Fix alignment problems reported by checkpatch]
CVSS 3.1 score
5.5
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Weakness type
CWE-369CVE-2026-31770 is a Divide By Zero vulnerability
What is Divide By Zero?
The product divides a value by zero, causing a crash or unexpected behaviour. Learn more on MITRE CWE
Affected versions
Linux kernel versions
5.0
and later are affected. Fixed in
5.10.253,
5.15.203,
6.1.168,
6.6.134,
6.12.81,
6.18.22,
6.19.12,
7.0
and their respective stable series.
References
The following references provide additional information about CVE-2026-31770 including vendor advisories, patch commits, exploit details, and third-party analysis. Links are sourced from the NIST NVD database.
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PatchKernel patch commithttps://git.kernel.org/stable/c/243d55bd3f08cb15eee9d63f4716d4d4cdd760f5
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PatchKernel patch commithttps://git.kernel.org/stable/c/2502684b9e835de9a992ec47c3e6c6faabe3858d
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PatchKernel patch commithttps://git.kernel.org/stable/c/37ae8fadc74ed68e5bc364ffd17746d88e449ae3
Frequently asked questions
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What is CVE-2026-31770?
CVE-2026-31770 is a Medium severity Linux kernel vulnerability with a CVSS score of 5.5 out of 10 , classified as a Divide By Zero flaw (CWE-369) . It affects Linux kernel versions from 5.0 onward and has been patched in 5.10.253, 5.15.203, 6.1.168 and others. CVE-2026-31770 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
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What is the CVSS score for CVE-2026-31770?
CVE-2026-31770 has a CVSS score of 5.5 out of 10, rated Medium severity (CVSS 3.1). The vector string is
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H. -
Is there a patch available for CVE-2026-31770?
Yes — CVE-2026-31770 has been patched. Fixed versions include 5.10.253, 5.15.203, 6.1.168 and others. If you are running Linux kernel 5.0 or later up to the fix versions, apply the relevant patch for your kernel branch.
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Is CVE-2026-31770 actively exploited?
No — CVE-2026-31770 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.
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What is Divide By Zero (CWE-369)?
The product divides a value by zero, causing a crash or unexpected behaviour. View CWE-369 on MITRE CWE →