Use After Free in Linux
CVE-2021-47427
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.
Vulnerability class: Use-After-Free
EPSS: 0.002 (12.3th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
Affected products
- Linux — versions d39df158518ccc3bf24ee18082b5e100c8f014aa, 5.14, 0
- Linux Linux_kernel — versions 5.15
Weakness classification (CWE)
References
Frequently asked questions
- What is CVE-2021-47427?
- CVE-2021-47427 is a critical-severity vulnerability in Linux, classified under Use After Free. CVSS score: 9.8/10. Published 2024-05-21.
- How severe is CVE-2021-47427?
- Critical severity. CVSS v3 base score is 9.8 out of 10.