CVE-2021-25261

Local privilege vulnerability in Yandex Browser for Windows prior to 22.5.0.862 allows a local, low privileged, attacker to execute arbitary code with the SYSTEM privileges through manipulating symlinks to installation file during Yandex Browser update process.

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://yandex.com/bugbounty/i/hall-of-fame-browser/