CVE-2020-24490

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Moderate Moderate Impact What does this mean?
7.1 CVSS v3 Base Score

Description

A heap buffer overflow flaw was found in the way the Linux kernel’s Bluetooth implementation processed extended advertising report events. This flaw allows a remote attacker in an adjacent range to crash the system, causing a denial of service or to potentially execute arbitrary code on the system by sending a specially crafted Bluetooth packet. The highest threat from this vulnerability is to confidentiality, integrity, as well as system availability.

Statement

This issue is rated as having Moderate impact because the system needs to be actively scanning while the attacker is sending the advertisements in order to be exploited.

This issue only affects the Linux kernel version as shipped with the Red Hat Enterprise Linux 8.3 GA release, kernel-4.18.0-240.el8 (and any kernel derived from this release such as kernel rt-4.18.0-240.rt7.54.el8). Red Hat was unable to include the fixes in the GA release, as the Red Hat Enterprise Linux 8.3 GA release was in its final stages of release preparation when CVE-2020-24490 was made public. All of the subsequent Red Hat Enterprise Linux 8 kernel versions, including the version included in the so-called 0day (released on the same day or very close to that day) erratum, contain the fix, thus immune to this issue.

Mitigation

The only way to mitigate these vulnerabilities on the operating system level is to disable the Bluetooth functionality via blacklisting kernel modules in the Linux kernel. The kernel modules can be prevented from being loaded by using system-wide modprobe rules. How to disable Bluetooth modules instructions are available on the Customer Portal at https://access.redhat.com/solutions/2682931.

Alternatively Bluetooth can be disabled within the hardware or at BIOS level which will also provide an effective mitigation as the kernel will not be able to detect that Bluetooth hardware is present on the system.

Additional Information

External References

Content from www.cve.org is not included.https://www.cve.org/CVERecord?id=CVE-2020-24490

Content from nvd.nist.gov is not included.https://nvd.nist.gov/vuln/detail/CVE-2020-24490

Content from git.kernel.org is not included.https://git.kernel.org/pub/scm/linux/kernel/git/bluetooth/bluetooth-next.git/commit/?id=a2ec905d1e160a33b2e210e45ad30445ef26ce0e

Content from github.com is not included.https://github.com/google/security-research/security/advisories/GHSA-ccx2-w2r4-x649

Content from www.intel.com is not included.https://www.intel.com/content/www/us/en/security-center/advisory/intel-sa-00435.html

Affected Packages and Issued Red Hat Security Errata

Products / Services Components State Errata
Red Hat Enterprise Linux 5 kernel Not affected
Red Hat Enterprise Linux 6 kernel Not affected
Red Hat Enterprise Linux 7 kernel Not affected
Red Hat Enterprise Linux 7 kernel-alt Not affected
Red Hat Enterprise Linux 7 kernel-rt Not affected
Red Hat Enterprise Linux 8 kernel Fixed RHSA-2020:4685
Red Hat Enterprise Linux 8 kernel-rt Fixed RHSA-2020:4686
Red Hat Enterprise MRG 2 kernel-rt Not affected
Unless explicitly stated as not affected, all previous versions of packages in any minor update stream of a product listed here should be assumed vulnerable, although may not have been subject to full analysis.

Common Vulnerability Scoring System (CVSS) Score Details

Important note

CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authorities (CNA) source for its products and services (see Red Hat classifications ).

CVSS v3 Score Breakdown Red Hat NVD
CVSS v3 Base Score 7.1 6.5
Attack Vector Adjacent Network Adjacent Network
Attack Complexity High Low
Privileges Required None None
User Interaction Required None
Scope Unchanged Unchanged
Confidentiality Impact High None
Integrity Impact High None
Availability Impact High High

CVSS v3 Vector

Red Hat CVSS:3.1/AV:A/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H

NVD CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Frequently Asked Questions

Why is Red Hat's CVSS v3 score or Impact different from other vendors?

 For open source software shipped by multiple vendors, the CVSS base scores may vary for each vendor's version depending on the version they ship, how they ship it, the platform, and even how the software is compiled. This makes scoring of vulnerabilities difficult for third-party vulnerability databases such as NVD that only provide a single CVSS base score for each vulnerability. Red Hat scores reflect how a vulnerability affects our products specifically.

For more information, see https://access.redhat.com/solutions/762393.

My product is listed as "Under investigation" or "Affected", when will Red Hat release a fix for this vulnerability?
  • "Under investigation" doesn't necessarily mean that the product is affected by this vulnerability. It only means that our Analysis Team is still working on determining whether the product is affected and how it is affected.
  • "Affected" means that our Analysis Team has determined that this product is affected by this vulnerability and might release a fix to address this in the near future.

What can I do if my product is listed as "Will not fix"?

 A "will not fix" status means that a fix for an affected product version is not planned or not possible due to complexity, which may create additional risk.

Available options depend mostly on the Impact of the vulnerability and the current Life Cycle phase of your product. Overall, you have the following options:
  • Upgrade to a supported product version that includes a fix for this vulnerability (recommended).
  • Apply a mitigation (if one exists).
  • Open a This content is not included.support case to request a prioritization of releasing a fix for this vulnerability.

What can I do if my product is listed as "Fix deferred"?

 A deferred status means that a fix for an affected product version is not guaranteed due to higher-priority development work.

Available options depend mostly on the Impact of the vulnerability and the current Life Cycle phase of your product. Overall, you have the following options:
  • Apply a mitigation (if one exists).
  • Open a This content is not included.support case to request a prioritization of releasing a fix for this vulnerability.
  • Red Hat Engineering focuses on addressing high-priority issues based on their complexity or limited lifecycle support. Therefore, lower-priority issues will not receive immediate fixes.

What is a mitigation?

 A mitigation is an action that can be taken to reduce the impact of a security vulnerability, without deploying any fixes.

I have a Red Hat product but it is not in the above list, is it affected?

 The listed products were found to include one or more of the components that this vulnerability affects. These products underwent a thorough evaluation to determine their affectedness by this vulnerability. Note that layered products (such as container-based offerings) that consume affected components from any of the products listed in this table may be affected and are not represented.

Why is my security scanner reporting my product as vulnerable to this vulnerability even though my product version is fixed or not affected?

 In order to maintain code stability and compatibility, Red Hat usually does not rebase packages to entirely new versions. Instead, we backport fixes and new features to an older version of the package we distribute. This can result in some security scanners that only consider the package version to report the package as vulnerable. To avoid this, we suggest that you use an approved vulnerability scanner from our This content is not included.Red Hat Vulnerability Scanner Certification program.