CVE-2021-27363Public exploit

Kernel-address disclosure via world-readable iSCSI transport handle

Published Mar 7, 2021 · Updated Aug 3, 2024

Kernel pointer disclosure in the Linux kernel through 5.11.3 allows local users to read an iSCSI transport structure address via sysfs. The show_transport_handle function formats the transport handle, which is the address of a global iscsi_transport structure, into a world-readable sysfs attribute. An iSCSI transport must be registered and scsi_transport_iscsi loaded; the disclosed pointer defeats KASLR for the module and supports chained local exploitation.

CVSS severity4.4
Medium
EPSS probability0.71%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Kernel pointer disclosure in the Linux kernel through 5.11.3 allows local users to read an iSCSI transport structure address via sysfs. The show_transport_handle function formats the transport handle, which is the address of a global iscsi_transport structure, into a world-readable sysfs attribute. An iSCSI transport must be registered and scsi_transport_iscsi loaded; the disclosed pointer defeats KASLR for the module and supports chained local exploitation.

The record

CVE
CVE-2021-27363
Published
Mar 7, 2021
Updated
Aug 3, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
Unavailable
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Mar 7, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 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 privilegesauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

4.4NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:L
3.6NVDAV:L/AC:L/Au:N/C:P/I:N/A:P

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 exploitPublished

Weakness, pattern, technique

No sourced classifications are available.

Public exploit references

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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