CVE-2021-47216

Kernel-address disclosure via unhashed SCSI pointer formatting

Published Apr 10, 2024 · Updated May 11, 2026

Kernel-address disclosure in the advansys SCSI driver in Linux allows local users to read raw pointers from per-adapter proc entries. The asc_prt_adv_board_info function casts v->iop_base to unsigned long and formats it with %lx instead of hashing it with %p. Exposure requires an AdvanSys SCSI host and access to its proc entry; the disclosed address reveals kernel memory-layout information.

CVSS severity5.5
Medium
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

Kernel-address disclosure in the advansys SCSI driver in Linux allows local users to read raw pointers from per-adapter proc entries. The asc_prt_adv_board_info function casts v->iop_base to unsigned long and formats it with %lx instead of hashing it with %p. Exposure requires an AdvanSys SCSI host and access to its proc entry; the disclosed address reveals kernel memory-layout information.

The record

CVE
CVE-2021-47216
Published
Apr 10, 2024
Updated
May 11, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
T1005
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Apr 10, 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=3.10
  2. Affected versionversion=31491e1ac425edc6b80a670a71ac8d2dfdd78417 <055eced3edf5b675d12189081303f6285ef26511
  3. Affected versionversion=31491e1ac425edc6b80a670a71ac8d2dfdd78417 <06d7d12efb5c62db9dea15141ae2b322c2719515
  4. Affected versionversion=31491e1ac425edc6b80a670a71ac8d2dfdd78417 <27490ae6a85a70242d80615ca74d0362a820d6a7
  5. Affected versionversion=31491e1ac425edc6b80a670a71ac8d2dfdd78417 <5612287991debe310c914600599bd59511ababfb
  6. Affected versionversion=31491e1ac425edc6b80a670a71ac8d2dfdd78417 <ad19f7046c24f95c674fbea21870479b2b9f5bab
  7. Affected versionversion=31491e1ac425edc6b80a670a71ac8d2dfdd78417 <cc248790bfdcf879e3094fa248c85bf92cdf9dae
  8. Affected versionversion=31491e1ac425edc6b80a670a71ac8d2dfdd78417 <d4996c6eac4c81b8872043e9391563f67f13e406
  9. Affected versionversion=31491e1ac425edc6b80a670a71ac8d2dfdd78417 <f5a0ba4a9b5e70e7b2f767636d26523f9d1ac59d

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=3.10; version=31491e1ac425edc6b80a670a71ac8d2dfdd78417 <055eced3edf5b675d12189081303f6285ef26511; version=31491e1ac425edc6b80a670a71ac8d2dfdd78417 <06d7d12efb5c62db9dea15141ae2b322c2719515; version=31491e1ac425edc6b80a670a71ac8d2dfdd78417 <27490ae6a85a70242d80615ca74d0362a820d6a7; version=31491e1ac425edc6b80a670a71ac8d2dfdd78417 <5612287991debe310c914600599bd59511ababfb; version=31491e1ac425edc6b80a670a71ac8d2dfdd78417 <ad19f7046c24f95c674fbea21870479b2b9f5bab; version=31491e1ac425edc6b80a670a71ac8d2dfdd78417 <cc248790bfdcf879e3094fa248c85bf92cdf9dae; version=31491e1ac425edc6b80a670a71ac8d2dfdd78417 <d4996c6eac4c81b8872043e9391563f67f13e406; version=31491e1ac425edc6b80a670a71ac8d2dfdd78417 <f5a0ba4a9b5e70e7b2f767636d26523f9d1ac59d

Published CVSS scores

5.5NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

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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

T1005Data from Local System

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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