What’s Vulnerable › Vulnerabilities

CVE-2021-20133

• Severity: medium (CVSS 6.1 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 2.1% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2021-12-30 · updated 2026-06-17
• Weakness: CWE-22

Description

Quagga Services on D-Link DIR-2640 less than or equal to version 1.11B02 are affected by an absolute path traversal vulnerability that allows a remote, authenticated attacker to set the "message of the day" banner to any file on the system, allowing them to read all or some of the contents of those files. Such sensitive information as hashed credentials, hardcoded plaintext passwords for other services, configuration files, and private keys can be disclosed in this fashion. Improper handling of filenames that identify virtual resources, such as "/dev/urandom" allows an attacker to effect a denial of service attack against the command line interfaces of the Quagga services (zebra and ripd).

Affected products

• Quagga Services on D-Link DIR-2640 Routers: through 1.11b02

References

• https://www.tenable.com/security/research/tra-2021-44
• https://www.tenable.com/security/research/tra-2021-44

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