CVE-2020-15680

5.3 mediumEPSS 0.9%

Medium (5.3) in mozilla firefox. EPSS 0.9% chance of exploitation in the next 30 days.

If a valid external protocol handler was referenced in an image tag, the resulting broken image size could be distinguished from a broken image size of a non-existent protocol handler. This allowed an attacker to successfully probe whether an external protocol handler was registered. This vulnerability affects Firefox < 82.

Severity

CVSS 3.1

5.3 medium

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

EPSS: 0.9% chance of exploitation in the next 30 days; higher than 61% of CVEs (scores of 2026-10-31)
Published: 2020-10-22
Modified: 2026-06-17
Record from: the NVD, synced 2026-10-19

Affected

mozilla:firefox

References

https://bugzilla.mozilla.org/show_bug.cgi?id=1658881
https://www.mozilla.org/security/advisories/mfsa2020-45/
https://bugzilla.mozilla.org/show_bug.cgi?id=1658881
https://www.mozilla.org/security/advisories/mfsa2020-45/

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