Linux Kernel up to 5.6.11 fuse Filesystem resource consumption

Summaryinfo

A vulnerability was found in Linux Kernel up to 5.6.11 and classified as problematic. Affected is an unknown function of the component fuse Filesystem. The manipulation results in resource consumption. This vulnerability is identified as CVE-2019-20794. The attack can be executed remotely. There is not any exploit available.

Detailsinfo

A vulnerability, which was classified as problematic, was found in Linux Kernel up to 5.6.11 (Operating System). Affected is an unknown code of the component fuse Filesystem. The manipulation with an unknown input leads to a resource consumption vulnerability. CWE is classifying the issue as CWE-400. The product does not properly control the allocation and maintenance of a limited resource, thereby enabling an actor to influence the amount of resources consumed, eventually leading to the exhaustion of available resources. This is going to have an impact on availability. CVE summarizes:

An issue was discovered in the Linux kernel 4.18 through 5.6.11 when unprivileged user namespaces are allowed. A user can create their own PID namespace, and mount a FUSE filesystem. Upon interaction with this FUSE filesystem, if the userspace component is terminated via a kill of the PID namespace's pid 1, it will result in a hung task, and resources being permanently locked up until system reboot. This can result in resource exhaustion.

The weakness was released 05/09/2020 (GitHub Repository). The advisory is shared for download at github.com. This vulnerability is traded as CVE-2019-20794 since 05/09/2020. It is possible to launch the attack remotely. A authentication is needed for exploitation. There are neither technical details nor an exploit publicly available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 05/10/2020). The MITRE ATT&CK project declares the attack technique as T1499.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 5.6.0
• 5.6.1
• 5.6.2
• 5.6.3
• 5.6.4
• 5.6.5
• 5.6.6
• 5.6.7
• 5.6.8
• 5.6.9
• 5.6.10
• 5.6.11

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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