What’s Vulnerable › Vulnerabilities

CVE-2020-15677

• Severity: medium (CVSS 6.1 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 1.7% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2020-10-01 · updated 2026-06-17
• Weakness: CWE-601

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.

Affected products

• Debian Linux: 9.0, 10.0
• Mozilla Firefox: before 81.0 — fixed in 81.0
• Mozilla Firefox ESR: before 78.3 — fixed in 78.3
• Mozilla Thunderbird: before 78.3 — fixed in 78.3
• openSUSE Leap: 15.1, 15.2

How to fix

Upgrade to a fixed version: Mozilla Firefox 81.0; Mozilla Firefox ESR 78.3; Mozilla Thunderbird 78.3. Check the vendor advisory for mitigations.

References

• http://lists.opensuse.org/opensuse-security-announce/2020-10/msg00074.html
• http://lists.opensuse.org/opensuse-security-announce/2020-10/msg00077.html
• https://bugzilla.mozilla.org/show_bug.cgi?id=1641487
• https://lists.debian.org/debian-lts-announce/2020/10/msg00020.html
• https://security.gentoo.org/glsa/202010-02
• https://www.debian.org/security/2020/dsa-4770
• https://www.mozilla.org/security/advisories/mfsa2020-42/
• https://www.mozilla.org/security/advisories/mfsa2020-43/
• https://www.mozilla.org/security/advisories/mfsa2020-44/
• http://lists.opensuse.org/opensuse-security-announce/2020-10/msg00074.html
• http://lists.opensuse.org/opensuse-security-announce/2020-10/msg00077.html
• https://bugzilla.mozilla.org/show_bug.cgi?id=1641487

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