What’s Vulnerable › Vulnerabilities

CVE-2020-26887

• Severity: high (CVSS 7.8 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 1.4% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2020-10-23 · updated 2026-06-17

Description

FRITZ!OS before 7.21 on FRITZ!Box devices allows a bypass of a DNS Rebinding protection mechanism.

Affected products

• Avm Fritz!Box 7490 Firmware: before 7.21 — fixed in 7.21

How to fix

Upgrade to a fixed version: Avm Fritz!Box 7490 Firmware 7.21. Check the vendor advisory for mitigations.

References

• http://packetstormsecurity.com/files/159606/FRITZ-Box-7.20-DNS-Rebinding-Protection-Bypass.html
• https://en.avm.de/news/
• https://www.redteam-pentesting.de/en/advisories/-advisories-publicised-vulnerability-analyses
• http://packetstormsecurity.com/files/159606/FRITZ-Box-7.20-DNS-Rebinding-Protection-Bypass.html
• https://en.avm.de/news/
• https://www.redteam-pentesting.de/en/advisories/-advisories-publicised-vulnerability-analyses

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