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Vulnerability record · CVE-2021-27363 · published 7 March 2021

CVE-2021-27363: Linux kernel vulnerability

Linux · Linux Kernel

An issue was discovered in the Linux kernel through 5.11.3. A kernel pointer leak can be used to determine the address of the iscsi_transport structure. When an iSCSI transport is registered with the iSCSI subsystem, the transport's handle is available to unprivileged users via the sysfs file system, at /sys/class/iscsi_transport/$TRANSPORT_NAME/handle. When read, the show_transport_handle function (in drivers/scsi/scsi_transport_iscsi.c) is called, which leaks the handle. This handle is actually the pointer to an iscsi_transport struct in the kernel module's global variables.

4.4 CVSS 3.1 Medium EPSS 0.71% · top 47.7%
4.4CVSS 3.1 base score, v2 3.6
0.71%EPSS exploitation probability, 30 days
NoNot in CISA KEV
4Affected product versions listed by NVD
16References, 2 tagged exploit
17 Jun 2026Last modified by NVD

Description

An issue was discovered in the Linux kernel through 5.11.3. A kernel pointer leak can be used to determine the address of the iscsi_transport structure. When an iSCSI transport is registered with the iSCSI subsystem, the transport's handle is available to unprivileged users via the sysfs file system, at /sys/class/iscsi_transport/$TRANSPORT_NAME/handle. When read, the show_transport_handle function (in drivers/scsi/scsi_transport_iscsi.c) is called, which leaks the handle. This handle is actually the pointer to an iscsi_transport struct in the kernel module's global variables.

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:L

Affected products

4 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
http://packetstormsecurity.com/files/162117/Kernel-Live-Patch-Security-Notice-LSN-0075-1.html Third Party AdvisoryVDB Entry
http://www.openwall.com/lists/oss-security/2021/03/06/1 Mailing ListPatchThird Party Advisory
https://blog.grimm-co.com/2021/03/new-old-bugs-in-linux-kernel.html ExploitThird Party Advisory
https://bugzilla.suse.com/show_bug.cgi?id=1182716 Issue TrackingThird Party Advisory
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=688e8128b7a92df982709a4137ea4588d16f24aa Mailing ListPatchVendor Advisory
https://lists.debian.org/debian-lts-announce/2021/03/msg00010.html Mailing ListThird Party Advisory
https://lists.debian.org/debian-lts-announce/2021/03/msg00035.html Third Party Advisory
https://security.netapp.com/advisory/ntap-20210409-0001/ Third Party Advisory
http://packetstormsecurity.com/files/162117/Kernel-Live-Patch-Security-Notice-LSN-0075-1.html Third Party AdvisoryVDB Entry
http://www.openwall.com/lists/oss-security/2021/03/06/1 Mailing ListPatchThird Party Advisory
https://blog.grimm-co.com/2021/03/new-old-bugs-in-linux-kernel.html ExploitThird Party Advisory
https://bugzilla.suse.com/show_bug.cgi?id=1182716 Issue TrackingThird Party Advisory
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=688e8128b7a92df982709a4137ea4588d16f24aa Mailing ListPatchVendor Advisory
https://lists.debian.org/debian-lts-announce/2021/03/msg00010.html Mailing ListThird Party Advisory
https://lists.debian.org/debian-lts-announce/2021/03/msg00035.html Third Party Advisory
https://security.netapp.com/advisory/ntap-20210409-0001/ Third Party Advisory

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Source: NIST National Vulnerability Database (record CVE-2021-27363), CISA KEV, FIRST EPSS (scores of 2026-10-13). This page is refreshed as NVD updates the record.