Skip to content
Noroxi
NVD / CVE Program· CNA Linux

CVE-2025-38312: fbdev: core: fbcvt: avoid division by 0 in fb_cvt_hperiod()

MediumCVSS 5.5 · v3.1—No exploit Fix available

Noroxi assessment

Priority: Monitor (action score 22/100)

  • The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
  • Probability of exploitation in the next 30 days: 0.19% (FIRST EPSS).
  • Someone with local access to the system can trigger it. A low-privileged account is enough. No user action is required. No special conditions are required; it is repeatable.
  • Fixed version: Linux Linux 2d63433e8eaa3c91b2948190e395bc67009db0d9, 3f6dae09fc8c306eb70fdfef70726e1f154e173a, 53784073cbad18f75583fd3da9ffdfc4d1f05405; azl3 kernel 6.6.92.2-2 on Azure Linux 3.0 6.6.96.1-1; azl3 kernel 6.6.96.1-1 on Azure Linux 3.0 6.6.96.1-1.

Low priority for now. Upgrade to Linux Linux 2d63433e8eaa3c91b2948190e395bc67009db0d9, 3f6dae09fc8c306eb70fdfef70726e1f154e173a, 53784073cbad18f75583fd3da9ffdfc4d1f05405; azl3 kernel 6.6.92.2-2 on Azure Linux 3.0 6.6.96.1-1; azl3 kernel 6.6.96.1-1 on Azure Linux 3.0 6.6.96.1-1 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

In the Linux kernel, the following vulnerability has been resolved: fbdev: core: fbcvt: avoid division by 0 in fb_cvt_hperiod() In fb_find_mode_cvt(), iff mode->refresh somehow happens to be 0x80000000, cvt.f_refresh will become 0 when multiplying it by 2 due to overflow. It's then passed to fb_cvt_hperiod(), where it's used as a divider -- division by 0 will result in kernel oops. Add a sanity check for cvt.f_refresh to avoid such overflow... Found by Linux Verification Center (linuxtesting.org) with the Svace static analysis tool.

Published
Jul 10, 2025
Updated
Nov 5, 2026
EPSS
0.1% · 9th percentile

Report tools

JSON

Action score

22

Monitor

Low priority for now.

CVSS
22 / 40 · 5.5 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.1%

CISA SSVC decision

Exploitation
none
Automatable
no
Technical impact
partial

Vulnrichment: CISA's decision-tree inputs.

Get told when this record changes

  • Not in KEV: no record of exploitation in the wild
  • No public exploit code on record
  • A fix has been released

If any of these changes, we'll tell you in the daily email digest.

Follow CVE-2025-38312

When you'll hear from us

  • when it enters CISA KEV
  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

One daily email digest (06:00 UTC); connect a webhook for KEV listings and weaponized exploits every 10 minutes on paid plans, on the hour on the free plan.

Your free account also gets you

  • CVE alerts: add the products and versions you run, get the new CVEs that affect them
  • Uptime monitoring: 1 site, instant email when it goes down
  • Add your domain: subdomains and takeover risk scanned every week (1 domain)
  • 10 scans an hour on the security tools, at most 30 a day (3 a day without an account), an API key and MCP
  • All your scans in one panel: findings, what changed in the last scan, a report per domain or per client (PDF, share link)
All free tools

Sign up with email · Have an account? Sign in

Free account, no card. Unfollow any time.

Don't want an account? Get "Exploited this week" by email every MondayDon't want an account? RSS feed for linux records
Is your version affected? Check it

Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

We use this product, ask for help

Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

VendorProduct
linuxlinux kernel
debiandebian linux

Versions reported by the vendor

Affected version ranges reported by the assigning authority (Linux). Independent of NVD's CPE analysis and usually ahead of it.

  • Linux Linux

    • 2.6.14affected
    • 96fe6a2109db29cd15b90a093c16e6cb4b19371a and later · before 9027ce4c037b566b658b8939a76326b7125e3627affected · git
    • 96fe6a2109db29cd15b90a093c16e6cb4b19371a and later · before 610f247f2772e4f92b63442125a1b7ade79898d8affected · git
    • 96fe6a2109db29cd15b90a093c16e6cb4b19371a and later · before 2d63433e8eaa3c91b2948190e395bc67009db0d9affected · git
    • 96fe6a2109db29cd15b90a093c16e6cb4b19371a and later · before 54947530663edcbaaee1314c01fdd8c72861b124affected · git
    • 96fe6a2109db29cd15b90a093c16e6cb4b19371a and later · before ab91647acdf43b984824776559a452212eaeb21aaffected · git
    • 96fe6a2109db29cd15b90a093c16e6cb4b19371a and later · before b235393b9f43ff86a38ca2bde6372312ea215dc5affected · git
    • 96fe6a2109db29cd15b90a093c16e6cb4b19371a and later · before 53784073cbad18f75583fd3da9ffdfc4d1f05405affected · git
    • 96fe6a2109db29cd15b90a093c16e6cb4b19371a and later · before 3f6dae09fc8c306eb70fdfef70726e1f154e173aaffected · git
    • before 2.6.14not affected · semver
Affected versions · NVD (8)

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • debian debian linux11.0
  • linux linux kernel5.5 and later · before 5.10.239
  • linux linux kernel5.11 and later · before 5.15.186
  • linux linux kernel5.16 and later · before 6.1.142
  • linux linux kernel2.6.14 and later · before 5.4.295
  • linux linux kernel6.7 and later · before 6.12.34
  • linux linux kernel6.13 and later · before 6.15.3
  • linux linux kernel6.2 and later · before 6.6.94

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
Debian:12linuxbefore 6.1.147-16.1.147-1
Debian:13linuxbefore 6.12.35-16.12.35-1

Same product

linux: all records

Other highest-scoring records for the same primary product.

  • CVE-2026-31431crypto: algif_aead - Revert to operating out-of-placeKEV
    90Now
  • CVE-2022-0847A flaw was found in the way the "flags" member of the new pipe buffer structure was lacking proper initialization in copy_page_to_iter_pipe…KEV
    89Now
  • CVE-2021-22555Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACEKEV
    85Now

Published before and after this one in the same product

  • ← EarlierCVE-2025-38310Jul 10, 2025 · seg6: Fix validation of nexthop addresses
    22Monitor
  • ← EarlierCVE-2025-38311Jul 10, 2025 · iavf: get rid of the crit lock
    22Monitor
  • Later →CVE-2025-38315Jul 10, 2025 · Bluetooth: btintel: Check dsbr size from EFI variable
    22Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
Linux Linux2d63433e8eaa3c91b2948190e395bc67009db0d9Vendor (CNA)
Linux Linux3f6dae09fc8c306eb70fdfef70726e1f154e173aVendor (CNA)
Linux Linux53784073cbad18f75583fd3da9ffdfc4d1f05405Vendor (CNA)
Linux Linux54947530663edcbaaee1314c01fdd8c72861b124Vendor (CNA)
Linux Linux610f247f2772e4f92b63442125a1b7ade79898d8Vendor (CNA)
Linux Linux9027ce4c037b566b658b8939a76326b7125e3627Vendor (CNA)
Linux Linuxab91647acdf43b984824776559a452212eaeb21aVendor (CNA)
Linux Linuxb235393b9f43ff86a38ca2bde6372312ea215dc5Vendor (CNA)
azl3 kernel 6.6.92.2-2 on Azure Linux 3.06.6.96.1-1 · CBL-Mariner ReleasesMicrosoft (MSRC)
azl3 kernel 6.6.96.1-1 on Azure Linux 3.06.6.96.1-1 · CBL-Mariner ReleasesMicrosoft (MSRC)
debian:linux6.1.147-1 · Debian:12Package registry (OSV)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

  • CVE-2024-26945435 days apartcrypto: iaa - Fix nr_cpus < nr_iaa case
    33Monitor
  • CVE-2025-382970 days apartPM: EM: Fix potential division-by-zero error in em_compute_costs()
    22Monitor
  • CVE-2025-382056 days apartdrm/amd/display: Avoid divide by zero by initializing dummy pitch to 1
    22Monitor
  • CVE-2025-381267 days apartnet: stmmac: make sure that ptp_rate is not 0 before configuring timestamping
    22Monitor
  • CVE-2022-5001022 days apartvideo: fbdev: i740fb: Check the argument of i740_calc_vclk()
    22Monitor
  • CVE-2022-5010222 days apartvideo: fbdev: arkfb: Fix a divide-by-zero bug in ark_set_pixclock()
    22Monitor

Not on record for this CVE: EPSS history · patch commit or PR link · researcher credit · public bounty program.

Technical details

Attack conditions

  • Someone with local access to the system can trigger it.
  • A low-privileged account is enough.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
none
Integrity
none
Availability
high · the service can be disrupted
Attack vector
Local
Attack complexity
Low
Privileges required
Low
User interaction
None
Scope
Unchanged
Confidentiality impact
None
Integrity impact
None
Availability impact
High

Weakness class (CWE)

CWE-369 · Divide By Zero

CVSS vector

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

nvd-primary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

MITRE has no CAPEC/ATT&CK mapping for this CWE.

References

Show all references (10 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records