CVE-2021-46965

Kernel stack disclosure via mis-scaled byte offset

Published Feb 27, 2024 · Updated May 11, 2026

An out-of-bounds read in the Linux Baikal-T1 ROM driver allows local users to read kernel stack data through an affected MTD mapping. In drivers/mtd/maps/physmap-bt1-rom.c, pointer arithmetic advances from a u32 object in four-byte units even though the offset represents bytes, causing reads beyond the object into adjacent stack memory. The published assessment requires local low-privileged access and bounds the result to kernel-memory disclosure and service interruption on systems using this driver.

CVSS severity7.1
High
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

An out-of-bounds read in the Linux Baikal-T1 ROM driver allows local users to read kernel stack data through an affected MTD mapping. In drivers/mtd/maps/physmap-bt1-rom.c, pointer arithmetic advances from a u32 object in four-byte units even though the offset represents bytes, causing reads beyond the object into adjacent stack memory. The published assessment requires local low-privileged access and bounds the result to kernel-memory disclosure and service interruption on systems using this driver.

The record

CVE
CVE-2021-46965
Published
Feb 27, 2024
Updated
May 11, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
CWE-125
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Feb 27, 2024CVE publishedPublication date reported by the CVE source.
  2. May 11, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=5.10
  2. Affected versionversion=b3e79e7682e075326df8041b826b03453acacd0a <34ec706bf0b7c4ca249a729c1bcb91f706c7a7be
  3. Affected versionversion=b3e79e7682e075326df8041b826b03453acacd0a <4d786870e3262ec098a3b4ed10b895176bc66ecb
  4. Affected versionversion=b3e79e7682e075326df8041b826b03453acacd0a <4e4ebb827bf09311469ffd9d0c14ed40ed9747aa
  5. Affected versionversion=b3e79e7682e075326df8041b826b03453acacd0a <683313993dbe1651c7aa00bb42a041d70e914925

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=5.10; version=b3e79e7682e075326df8041b826b03453acacd0a <34ec706bf0b7c4ca249a729c1bcb91f706c7a7be; version=b3e79e7682e075326df8041b826b03453acacd0a <4d786870e3262ec098a3b4ed10b895176bc66ecb; version=b3e79e7682e075326df8041b826b03453acacd0a <4e4ebb827bf09311469ffd9d0c14ed40ed9747aa; version=b3e79e7682e075326df8041b826b03453acacd0a <683313993dbe1651c7aa00bb42a041d70e914925

Published CVSS scores

7.1NIST NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H

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 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-125Out-of-bounds Read

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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