CVE-2020-15677 Open redirect in Firefox

What is CVE-2020-15677?

CVE-2020-15677 is a medium-severity vulnerability in Debian Debian Linux, published on 1 Oct 2020. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

Official description

By exploiting an Open Redirect vulnerability on a website, an attacker could have spoofed the site displayed in the download file dialog to show the original site (the one suffering from the open redirect) rather than the site the file was actually downloaded from. This vulnerability affects Firefox < 81, Thunderbird < 78.3, and Firefox ESR < 78.3.

Weakness: CWE-601

Which versions are affected by CVE-2020-15677?

It affects 5 products.

Products include Debian Debian Linux, Mozilla Firefox, Mozilla Firefox Esr, Mozilla Thunderbird, Opensuse Leap.

How do I fix CVE-2020-15677?

Upgrade to a fixed version.

Is CVE-2020-15677 being exploited?

There is no known exploitation of CVE-2020-15677 in the wild and no public exploit code.

Other vulnerabilities in Debian Debian Linux

• CVE-2015-3306 ProFTPD Improper Access Control Exploited Critical 10.0
• CVE-2025-49113 RoundCube Webmail Deserialization of Untrusted Data Exploited Critical 9.9
• CVE-2026-24061 GNU InetUtils Argument Injection Exploited Critical 9.8
• CVE-2025-39682 Linux Kernel Improper Check for Unusual or Exceptional Conditions Exploited Critical 9.8
• CVE-2024-9680 Mozilla Firefox Use-After-Free Exploited Critical 9.8

All Debian Debian Linux vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as DEBIAN-CVE-2020-15677, GHSA-c2xm-2fm6-9338, UBUNTU-CVE-2020-15677.