#VU71689 Race condition in Utilities for Amazon Elastic File System (EFS) - CVE-2022-46174

Vulnerability identifier: #VU71689

Vulnerability risk: Low

CVSSv4.0: 1.1 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2022-46174

CWE-ID: CWE-362

Exploitation vector: Local

Exploit availability: No

Vulnerable software:
Utilities for Amazon Elastic File System (EFS)
Universal components / Libraries / Libraries used by multiple products

Vendor: Amazon Web Services

Description

The vulnerability allows a local user to perform a denial of service (DoS) attack.

The vulnerability exists due to a race condition within the Amazon EFS mount helper when using TLS to mount file systems. The mount helper allocates a local port for stunnel to receive NFS connections prior to applying the TLS tunnel. As a result, concurrent mount operations can allocate the same local port, leading to either failed mount operations or an inappropriate mapping from an EFS customer’s local mount points to that customer’s EFS file systems.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Utilities for Amazon Elastic File System (EFS): 1.0 - 1.34.3

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External links
https://github.com/aws/efs-utils/commit/f3a8f88167d55caa2f78aeb72d4dc1987a9ed62d
https://github.com/aws/efs-utils/issues/125
https://github.com/aws/efs-utils/security/advisories/GHSA-4fv8-w65m-3932

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Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.