CVE-2020-15648

Severity: medium (CVSS 6.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.1% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2020-08-10 · updated 2026-06-17
Weakness: CWE-1021

Description

Using object or embed tags, it was possible to frame other websites, even if they disallowed framing using the X-Frame-Options header. This vulnerability affects Thunderbird < 78 and Firefox < 78.0.2.

Affected products

Mozilla Firefox: before 78.0.2 — fixed in 78.0.2
Mozilla Thunderbird: before 78.0 — fixed in 78.0

How to fix

Upgrade to a fixed version: Mozilla Firefox 78.0.2; Mozilla Thunderbird 78.0. Check the vendor advisory for mitigations.

References

https://bugzilla.mozilla.org/show_bug.cgi?id=1644076
https://www.mozilla.org/security/advisories/mfsa2020-28/
https://www.mozilla.org/security/advisories/mfsa2020-29/
https://bugzilla.mozilla.org/show_bug.cgi?id=1644076
https://www.mozilla.org/security/advisories/mfsa2020-28/
https://www.mozilla.org/security/advisories/mfsa2020-29/

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