Access Restriction Bypass Affecting firefox-esr package, versions <45.0esr-1


Severity

Recommended
0.0
high
0
10

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Threat Intelligence

EPSS
1.5% (71st percentile)

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  • Snyk IDSNYK-ECHOLATEST-FIREFOXESR-18168550
  • published22 Jul 2026
  • disclosed13 Feb 2016

Introduced: 13 Feb 2016

CVE-2016-1949  (opens in a new tab)
CWE-264  (opens in a new tab)

How to fix?

Upgrade Echo:latest firefox-esr to version 45.0esr-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.

Mozilla Firefox before 44.0.2 does not properly restrict the interaction between Service Workers and plugins, which allows remote attackers to bypass the Same Origin Policy via a crafted web site that triggers spoofed responses to requests that use NPAPI, as demonstrated by a request for a crossdomain.xml file.

CVSS Base Scores

version 3.1