7.8
HIGH CVSS 3.1
CVE-2021-47111
xen-netback: take a reference to the RX task thread
Description

In the Linux kernel, the following vulnerability has been resolved: xen-netback: take a reference to the RX task thread Do this in order to prevent the task from being freed if the thread returns (which can be triggered by the frontend) before the call to kthread_stop done as part of the backend tear down. Not taking the reference will lead to a use-after-free in that scenario. Such reference was taken before but dropped as part of the rework done in 2ac061ce97f4. Reintroduce the reference taking and add a comment this time explaining why it's needed. This is XSA-374 / CVE-2021-28691.

INFO

Published Date :

March 15, 2024, 9:15 p.m.

Last Modified :

Feb. 27, 2025, 3:20 a.m.

Remotely Exploit :

No

Source :

416baaa9-dc9f-4396-8d5f-8c081fb06d67
Affected Products

The following products are affected by CVE-2021-47111 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Linux linux_kernel
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 HIGH [email protected]
Solution
Update the Linux kernel to address a use-after-free vulnerability in Xen netback.
  • Update the Linux kernel.
  • Run 'yum update kernel' to update the system.
Public PoC/Exploit Available at Github

CVE-2021-47111 has a 1 public PoC/Exploit available at Github. Go to the Public Exploits tab to see the list.

CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2021-47111 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2021-47111 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Ini adalah repository kumpulan CVE v.5

allcve cve cvelist newcve

Updated: 1 year, 4 months ago
2 stars 0 fork 0 watcher
Born at : March 24, 2024, 3:01 p.m. This repo has been linked 1214 different CVEs too.

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2021-47111 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2021-47111 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • Initial Analysis by [email protected]

    Feb. 27, 2025

    Action Type Old Value New Value
    Added CVSS V3.1 AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
    Added CWE CWE-416
    Added CPE Configuration OR *cpe:2.3:o:linux:linux_kernel:5.13:rc1:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:5.13:rc2:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:5.13:rc3:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:5.13:rc4:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:5.13:rc5:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 5.11 from (excluding) 5.12.10 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 5.5 from (excluding) 5.10.43
    Added Reference Type CVE: https://git.kernel.org/stable/c/107866a8eb0b664675a260f1ba0655010fac1e08 Types: Patch
    Added Reference Type kernel.org: https://git.kernel.org/stable/c/107866a8eb0b664675a260f1ba0655010fac1e08 Types: Patch
    Added Reference Type CVE: https://git.kernel.org/stable/c/6b53db8c4c14b4e7256f058d202908b54a7b85b4 Types: Patch
    Added Reference Type kernel.org: https://git.kernel.org/stable/c/6b53db8c4c14b4e7256f058d202908b54a7b85b4 Types: Patch
    Added Reference Type CVE: https://git.kernel.org/stable/c/caec9bcaeb1a5f03f2d406305355c853af10c13e Types: Patch
    Added Reference Type kernel.org: https://git.kernel.org/stable/c/caec9bcaeb1a5f03f2d406305355c853af10c13e Types: Patch
  • CVE Modified by af854a3a-2127-422b-91ae-364da2661108

    Nov. 21, 2024

    Action Type Old Value New Value
    Added Reference https://git.kernel.org/stable/c/107866a8eb0b664675a260f1ba0655010fac1e08
    Added Reference https://git.kernel.org/stable/c/6b53db8c4c14b4e7256f058d202908b54a7b85b4
    Added Reference https://git.kernel.org/stable/c/caec9bcaeb1a5f03f2d406305355c853af10c13e
  • CVE Modified by 416baaa9-dc9f-4396-8d5f-8c081fb06d67

    May. 28, 2024

    Action Type Old Value New Value
  • CVE Modified by 416baaa9-dc9f-4396-8d5f-8c081fb06d67

    May. 14, 2024

    Action Type Old Value New Value
  • CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67

    Mar. 15, 2024

    Action Type Old Value New Value
    Added Description In the Linux kernel, the following vulnerability has been resolved: xen-netback: take a reference to the RX task thread Do this in order to prevent the task from being freed if the thread returns (which can be triggered by the frontend) before the call to kthread_stop done as part of the backend tear down. Not taking the reference will lead to a use-after-free in that scenario. Such reference was taken before but dropped as part of the rework done in 2ac061ce97f4. Reintroduce the reference taking and add a comment this time explaining why it's needed. This is XSA-374 / CVE-2021-28691.
    Added Reference kernel.org https://git.kernel.org/stable/c/6b53db8c4c14b4e7256f058d202908b54a7b85b4 [No types assigned]
    Added Reference kernel.org https://git.kernel.org/stable/c/caec9bcaeb1a5f03f2d406305355c853af10c13e [No types assigned]
    Added Reference kernel.org https://git.kernel.org/stable/c/107866a8eb0b664675a260f1ba0655010fac1e08 [No types assigned]
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
Vulnerability Scoring Details
Base CVSS Score: 7.8
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality Impact
Integrity Impact
Availability Impact