CVE-2020-8948

The Sierra Wireless Windows Mobile Broadband Driver Packages (MBDP) before build 5043 allows an unprivileged user to overwrite arbitrary files in arbitrary folders using hard links. An unprivileged user could leverage this vulnerability to execute arbitrary code with system privileges.

Weakness

The product attempts to access a file based on the filename, but it does not properly prevent that filename from identifying a link or shortcut that resolves to an unintended resource.

Affected Software

Potential Mitigations

• Follow the principle of least privilege when assigning access rights to entities in a software system.
• Denying access to a file can prevent an attacker from replacing that file with a link to a sensitive file. Ensure good compartmentalization in the system to provide protected areas that can be trusted.

Related Attack Patterns

• https://cwe.mitre.org/data/definitions/132.html
• https://cwe.mitre.org/data/definitions/17.html
• https://cwe.mitre.org/data/definitions/35.html
• https://cwe.mitre.org/data/definitions/76.html

References

• https://danishcyberdefence.dk/blog/sierra_wireless
• https://source.sierrawireless.com/resources/airlink/software_reference_docs/technical-bulletin/sierra-wireless-technical-bulletin---swi-psa-2020-002-cve-2020-8948/#sthash.ByZB8ifG.dpbs