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Vulnerability record · public intelligence
CVE-2020-28974
UNKNOWN

CVE-2020-28974

Published Nov 20, 2020 · Updated Nov 3, 2026

Severity · CVSSUNKNOWN · Not scored
Known exploitationNot listed
EPSS / likelihood0.52%
QFinch risk scoreNot available

Original summary

Normalized public record · Updated Nov 3, 2026

A slab-out-of-bounds read in fbcon in the Linux kernel before 5.9.7 could be used by local attackers to read privileged information or potentially crash the kernel, aka CID-3c4e0dff2095. This occurs because KD_FONT_OP_COPY in drivers/tty/vt/vt.c can be used for manipulations such as font height.

Publisher and source text is retained separately from QFinch interpretation.

QFinch assessment

A slab-out-of-bounds read in fbcon in the Linux kernel before 5.9.7 could be used by local attackers to read privileged information or potentially crash the kernel, aka CID-3c4e0dff2095. This occurs because KD_FONT_OP_COPY in drivers/tty/vt/vt.c can be used for manipulations such as font height.

Evidence: public source records

Affected products

Affected scope reported by the available public evidence
Affected package, product or rangeFix status
Consult the referenced vendor advisory for affected versions.Consult source advisory

Matching a version is only one part of assessing exposure. QFinch has not assessed your environment on this public page.

Remediation

Apply the vendor-supported fixed release or mitigation, then verify the affected component is no longer reachable.

  1. Confirm the affected product and reachable code path exist in your environment.
  2. Apply the vendor-supported patch or mitigation from the primary advisory.
  3. Rescan the exact deployed revision and retain verification evidence.
Review primary references

Evidence coverage

FIRST-EPSSCVE-LIST-V5
SSVC priority
LOW
Confidence
Not available
Aliases
None reported

Scores appear only when corresponding evidence exists. Missing data is never interpreted as zero risk.

Sources and record history

  1. Patch commit ↗
  2. seclists.org ↗
  3. cdn.kernel.org ↗
  4. [oss-security] 20201124 Re: Linux kernel slab-out-of-bounds Read in fbcon ↗
  5. [debian-lts-announce] 20201210 [SECURITY] [DLA 2483-1] linux-4.19 security update ↗
  6. [debian-lts-announce] 20201218 [SECURITY] [DLA 2494-1] linux security update ↗
  7. security.netapp.com ↗

Record history

Published Nov 20, 2020 · Last refreshed Nov 3, 2026

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