Information Exposure Affecting firefox-esr package, versions <78.8.0esr-1


Severity

Recommended
0.0
medium
0
10

Snyk's Security Team recommends NVD's CVSS assessment. Learn more

Threat Intelligence

EPSS
1.37% (69th percentile)

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  • Snyk IDSNYK-ECHOLATEST-FIREFOXESR-18169267
  • published22 Jul 2026
  • disclosed26 Feb 2021

Introduced: 26 Feb 2021

CVE-2021-23973  (opens in a new tab)
CWE-209  (opens in a new tab)

How to fix?

Upgrade Echo:latest firefox-esr to version 78.8.0esr-1 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream firefox-esr package and not the firefox-esr package as distributed by Echo. See How to fix? for Echo:latest relevant fixed versions and status.

When trying to load a cross-origin resource in an audio/video context a decoding error may have resulted, and the content of that error may have revealed information about the resource. This vulnerability affects Firefox < 86, Thunderbird < 78.8, and Firefox ESR < 78.8.

CVSS Base Scores

version 3.1