7.8
HIGH
CVE-2021-28691
Xen Netback Linux Guest Use-After-Free Vulnerability
Description

Guest triggered use-after-free in Linux xen-netback A malicious or buggy network PV frontend can force Linux netback to disable the interface and terminate the receive kernel thread associated with queue 0 in response to the frontend sending a malformed packet. Such kernel thread termination will lead to a use-after-free in Linux netback when the backend is destroyed, as the kernel thread associated with queue 0 will have already exited and thus the call to kthread_stop will be performed against a stale pointer.

INFO

Published Date :

June 29, 2021, 12:15 p.m.

Last Modified :

April 6, 2022, 4:46 p.m.

Remotely Exploitable :

No

Impact Score :

5.9

Exploitability Score :

1.8
Affected Products

The following products are affected by CVE-2021-28691 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 Netapp h410c_firmware
2 Netapp cloud_backup
3 Netapp h300s_firmware
4 Netapp h500s_firmware
5 Netapp h700s_firmware
6 Netapp h410s_firmware
7 Netapp h300e_firmware
8 Netapp h500e_firmware
9 Netapp h700e_firmware
1 Linux linux_kernel
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2021-28691.

URL Resource
https://security.gentoo.org/glsa/202107-30 Third Party Advisory
https://security.netapp.com/advisory/ntap-20210805-0002/ Third Party Advisory
https://xenbits.xenproject.org/xsa/advisory-374.txt Third Party Advisory

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).

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

The following list is the news that have been mention CVE-2021-28691 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2021-28691 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.

  • CVE Modified by [email protected]

    May. 14, 2024

    Action Type Old Value New Value
  • Modified Analysis by [email protected]

    Apr. 06, 2022

    Action Type Old Value New Value
    Changed Reference Type https://security.gentoo.org/glsa/202107-30 No Types Assigned https://security.gentoo.org/glsa/202107-30 Third Party Advisory
    Changed Reference Type https://security.netapp.com/advisory/ntap-20210805-0002/ No Types Assigned https://security.netapp.com/advisory/ntap-20210805-0002/ Third Party Advisory
    Added CPE Configuration OR *cpe:2.3:a:netapp:cloud_backup:-:*:*:*:*:*:*:*
    Added CPE Configuration AND OR *cpe:2.3:o:netapp:h410c_firmware:-:*:*:*:*:*:*:* OR cpe:2.3:h:netapp:h410c:-:*:*:*:*:*:*:*
    Added CPE Configuration AND OR *cpe:2.3:o:netapp:h300s_firmware:-:*:*:*:*:*:*:* OR cpe:2.3:h:netapp:h300s:-:*:*:*:*:*:*:*
    Added CPE Configuration AND OR *cpe:2.3:o:netapp:h500s_firmware:-:*:*:*:*:*:*:* OR cpe:2.3:h:netapp:h500s:-:*:*:*:*:*:*:*
    Added CPE Configuration AND OR *cpe:2.3:o:netapp:h700s_firmware:-:*:*:*:*:*:*:* OR cpe:2.3:h:netapp:h700s:-:*:*:*:*:*:*:*
    Added CPE Configuration AND OR *cpe:2.3:o:netapp:h300e_firmware:-:*:*:*:*:*:*:* OR cpe:2.3:h:netapp:h300e:-:*:*:*:*:*:*:*
    Added CPE Configuration AND OR *cpe:2.3:o:netapp:h500e_firmware:-:*:*:*:*:*:*:* OR cpe:2.3:h:netapp:h500e:-:*:*:*:*:*:*:*
    Added CPE Configuration AND OR *cpe:2.3:o:netapp:h700e_firmware:-:*:*:*:*:*:*:* OR cpe:2.3:h:netapp:h700e:-:*:*:*:*:*:*:*
    Added CPE Configuration AND OR *cpe:2.3:o:netapp:h410s_firmware:-:*:*:*:*:*:*:* OR cpe:2.3:h:netapp:h410s:-:*:*:*:*:*:*:*
  • CVE Modified by [email protected]

    Aug. 05, 2021

    Action Type Old Value New Value
    Added Reference https://security.netapp.com/advisory/ntap-20210805-0002/ [No Types Assigned]
  • CVE Modified by [email protected]

    Jul. 12, 2021

    Action Type Old Value New Value
    Added Reference https://security.gentoo.org/glsa/202107-30 [No Types Assigned]
  • Initial Analysis by [email protected]

    Jul. 06, 2021

    Action Type Old Value New Value
    Added CVSS V2 NIST (AV:L/AC:L/Au:N/C:P/I:P/A:P)
    Added CVSS V3.1 NIST AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
    Changed Reference Type https://xenbits.xenproject.org/xsa/advisory-374.txt No Types Assigned https://xenbits.xenproject.org/xsa/advisory-374.txt Third Party Advisory
    Added CWE NIST CWE-416
    Added CPE Configuration OR *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 5.5.0 up to (excluding) 5.12.2
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.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2021-28691 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-2021-28691 weaknesses.

Exploit Prediction

EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days.

0.04 }} 0.00%

score

0.10264

percentile

CVSS31 - Vulnerability Scoring System
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality
Integrity
Availability