CVE-2020-36766

Kernel-memory disclosure via uninitialized structure padding

Published Sep 18, 2023 · Updated Sep 25, 2024

Information disclosure in the Linux kernel before 5.8.6 allows local users to read one byte of kernel memory through a CEC ioctl. In cec_adap_g_log_addrs(), direct structure assignment leaves a padding byte uninitialized before copy_to_user() returns the structure. Exploitation requires local access to a CEC device on specific hardware; the disclosed byte cannot alter kernel state or interrupt service.

CVSS severity3.3
Low
EPSS probability0.23%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Information disclosure in the Linux kernel before 5.8.6 allows local users to read one byte of kernel memory through a CEC ioctl. In cec_adap_g_log_addrs(), direct structure assignment leaves a padding byte uninitialized before copy_to_user() returns the structure. Exploitation requires local access to a CEC device on specific hardware; the disclosed byte cannot alter kernel state or interrupt service.

The record

CVE
CVE-2020-36766
Published
Sep 18, 2023
Updated
Sep 25, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
Unavailable
Attack vector
local
Privileges
Unavailable

Timeline

How it unfolded

  1. Sep 18, 2023CVE publishedPublication date reported by the CVE source.
  2. Sep 25, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectorlocal
Required privilegesUnavailable in this record.

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

3.3NIST NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
PrivilegesUnavailable
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

No sourced classifications are available.

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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