Vulnary
← back to the feed
Critical· 9.8official fix available

CVE-2021-47427

CVE-2021-47427 is a critical use-after-free vulnerability in the Linux kernel's iSCSI subsystem (CVSS 9.8, CWE-416). It was resolved by a kernel patch (commit d39df158518c) that fixes the handling of iscsi_task during abort handling. No known exploitation or public exploit has been reported.

publishedMay 21, 2024
last modifiedAug 4, 2026
sourcesNVD
severity · cvss
9.8
critical · how bad it is
exploitation · epss
<1%
37th percentile · chance of exploitation in 30 days
(ai-assisted) A model wrote this summary from the official data, so double-check it against the source before you act on it. Read the official advisory →
auto-deletes from the system
counting…on Sep 4, 2026

An official fix is available, so this entry is kept for 30 days and then removed automatically.

01

Who is affected

Linux kernel (including version 5.15 as listed in CPE data).

02

Real-world impact

An attacker could potentially execute arbitrary code, cause denial of service, or escalate privileges by exploiting the use-after-free condition.

03

Why this severity

The CVSS v3.1 base score of 9.8 reflects a network‑reachable attack with low complexity, no privileges or user interaction required, and high impacts to confidentiality, integrity, and availability.

04

What to do about it

official fix available
recommended steps
  1. 01Obtain the patch commit d39df158518c from the Linux kernel source.
  2. 02Apply the patch to the affected kernel version.
  3. 03Rebuild and reinstall the kernel.
  4. 04Reboot the system to load the patched kernel.

NVD-referenced vendor advisory

05

Timeline

  1. May 21, 2024 · May 21, 2024
    Published
    Disclosed and added to the National Vulnerability Database.
  2. Aug 4, 2026 · 2d ago
    Advisory updated
    The NVD record was last revised.
  3. Aug 5, 2026 · 1d ago
    Official fix available
    A vendor patch or mitigation now exists — see the remediation steps above.
06

How it’s attacked

Attack vectorNetwork (remote)
Attack complexityLow
Privileges requiredNone
User interactionNone needed
ScopeUnchanged
Confidentiality impactHigh
Integrity impactHigh
Availability impactHigh
07

References & advisories

(ai-assisted) A model wrote this summary from the official data, so double-check it against the source before you act on it. Read the official advisory →