CVE-2021-27363: Infoleak
A flaw was found in the way access to sessions and handles was handled in the iSCSI driver in the Linux kernel. A local user could use this flaw to leak iSCSI transport handle kernel address or end arbitrary iSCSI connections on the system.
Other sources
A pointer leak was discovered in the linux kernel that can be used to determine the address of the iscsitransportstructure.
— Red Hat
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 iscsitransport 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/iscsitransport/$TRANSPORTNAME/handle. When read, the showtransporthandle function (in drivers/scsi/scsitransportiscsi.c) is called, which leaks the handle. This handle is actually the pointer to an iscsitransport struct in the kernel module's global variables.
Affected Software
Remediation
Information
Patch Available
Event History
Parent advisories
This vulnerability appears in the following advisories.
Frequently Asked Questions
What is the severity of CVE-2021-27363?
CVE-2021-27363 is classified as a medium severity vulnerability.
How do I fix CVE-2021-27363?
To remediate CVE-2021-27363, users should upgrade to the patched kernel versions specified in the security advisories.
What impact does CVE-2021-27363 have on Linux kernel operations?
CVE-2021-27363 allows local users to leak kernel addresses or disrupt iSCSI connections, potentially affecting system stability.
Which Linux kernel versions are vulnerable to CVE-2021-27363?
CVE-2021-27363 affects various Linux kernel versions prior to the patched releases, including versions 3.10 and 4.18.
Who is affected by CVE-2021-27363?
Local users of systems running vulnerable versions of the Linux kernel are at risk from CVE-2021-27363.