CVE Intelligence
Unknown

CVE-2026-89821 — drm/amd/display: avoid divide-by-zero in __is_lut_linear()

In the Linux kernel, the following vulnerability has been resolved: drm/amd/display: avoid divide-by-zero in __is_lut_linear() __is_lut_linear() computes the expected value of each entry with expected = i * MAX_DRM_LUT_VALUE / (size - 1); If it is ever called with a single-entry LUT, size - 1 is zero and the kernel takes a divide error (#DE). A LUT with fewer than two entries cannot describe a linear mapping anyway, so return false early instead of dividing by zero.

Published Sep 16, 2026 · Updated Oct 19, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP, GitHub Security Advisories · CNA: Linux

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

No exploitation signal in the sources consulted so far.
How the score was calculated
  • EPSS 0.2% (30-day exploitation probability)+2

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation
Not confirmed
Not in CISA KEV — an absence of record, not proof it is unexploited.
EPSS FIRST
0.21%
ahead of 11% of scored CVEs · Oct 20, 2026
Affects
Linux
Linux
CVSS base
—
Score not published yet.

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

  1. Identify exposed assets running the affected vendor/product/version combinations (Linux Linux).
  2. No fix documented in the sources: reduce exposure and monitor the vendor advisory.
  3. Search available logs for exploit probes, errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

VendorProductVersionsStatusSource
Linux Linux ≥ 086247a4b2fba49800b27807f22bb894cd8363fb and < 2320626425f3af3a25b8afb6876f205b1c6d4e64≥ 086247a4b2fba49800b27807f22bb894cd8363fb and < d1e06d5dc8f12451ce71dc068342660a34476084≥ 086247a4b2fba49800b27807f22bb894cd8363fb and < c127ace7af2b40107947a6504391f94d6fd21734≥ 086247a4b2fba49800b27807f22bb894cd8363fb and < 4d5ee095a58461b2446d7a6eb0c14c2fe3eaab44≥ 086247a4b2fba49800b27807f22bb894cd8363fb and < 5f18cd1ba873e751bf5547407ad44ea34adfbe2f≥ 086247a4b2fba49800b27807f22bb894cd8363fb and < ee28fafb50f58b847509b5240b431ddec673bdfe≥ 086247a4b2fba49800b27807f22bb894cd8363fb and < 15ee43aad0df43dfd1dbb32e7d5b951745c4b87f≥ 086247a4b2fba49800b27807f22bb894cd8363fb and < 4f40873f8a4107df2b9c8e68c947c4fd0cd519d2
and 1 more version 4.17
Vulnerable CVE Program (cve.org) e CISA ADP

EPSS over time FIRST

Oct 15, 2026 → Oct 20, 2026 · 5 reading(s) · max 0.21%

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

  • Not enough vector or weakness data: use the affected application’s logs as a starting point.
application logs

Timeline

What happened to this CVE, newest first.

  • 2026
  • Record published
    Oct 15, 2026
  • Affected products added · linux/linux
    Oct 15, 2026 · CVE Program (cve.org) e CISA ADP
  • Source status changed · → Received
    Oct 15, 2026 · NIST National Vulnerability Database
  • Record created in this database
    Oct 15, 2026 · NIST National Vulnerability Database
  • CVE published
    Sep 16, 2026 · Linux

Source activity

Repeated readings are counted rather than listed.

  • 1× References added · Oct 19, 2026 – Oct 19, 2026
  • 1× Official description updated · Oct 15, 2026 – Oct 15, 2026

References

10 on the record

Elsewhere on this site

Linux
every CVE for this vendor

Related CVEs (same products)

  • CVE-2026-98866 sched/cache: Introduce task_struct->sched_cache_grp to fix UAF 2d
  • CVE-2026-98867 dm-pcache: bound the logical key offset from persistent memory 2d
  • CVE-2026-98868 dm-pcache: reject a kset that overruns its segment 2d
  • CVE-2026-98856 kprobes: Skip disarmed probes when checking optkprobe overlap 2d
  • CVE-2026-98857 ipvs: bound LBLCR and LBLC cache growth 2d
  • CVE-2026-98858 io_uring: fix task_work add use-after-free with SQPOLL 2d

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

  • No CVSS score published by NVD, the CNA, CISA or GitHub so far.
  • No fixed version, patch or mitigation documented.
  • No CISA SSVC assessment.
  • No CWE classification.
  • No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
  • No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
  • No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2026-89821 is "drm/amd/display: avoid divide-by-zero in __is_lut_linear()", rated Unknown. It affects Linux (Linux); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. EPSS 0.21% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

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