CVE-2021-47427

CriticalCVSS 9.8

Published: 21/05/2024(UTC)Updated: 04/08/2026(UTC)Translated: 05/08/2026(UTC)NVD NIST

Exploitation Probability (EPSS)

Low risk

0.46%

37th percentile - higher than 37% of all known CVEs

Summary

In the Linux kernel's scsi iscsi module, a use-after-free bug exists in task abort handling. The fix reverts a goto to common cleanup code and moves iscsi_get_conn() after checking task validity.

Risk Assessment

This vulnerability could cause memory corruption in iSCSI drivers, potentially leading to system crashes or privilege escalation.

Recommendation

Apply the Linux kernel update containing the fix for CVE-2021-47427. Prioritize systems with iSCSI.

Original NVD description (English source)

In the Linux kernel, the following vulnerability has been resolved: scsi: iscsi: Fix iscsi_task use after free Commit d39df158518c ("scsi: iscsi: Have abort handler get ref to conn") added iscsi_get_conn()/iscsi_put_conn() calls during abort handling but then also changed the handling of the case where we detect an already completed task where we now end up doing a goto to the common put/cleanup code. This results in a iscsi_task use after free, because the common cleanup code will do a put on the iscsi_task. This reverts the goto and moves the iscsi_get_conn() to after we've checked if the iscsi_task is valid.