Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution') Affecting firefox-esr package, versions <91.9.1esr-1


Severity

Recommended
0.0
high
0
10

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Threat Intelligence

Exploit Maturity
Proof of Concept
EPSS
26.71% (98th percentile)

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  • Snyk IDSNYK-ECHOLATEST-FIREFOXESR-18168820
  • published22 Jul 2026
  • disclosed22 Dec 2022

Introduced: 22 Dec 2022

CVE-2022-1802  (opens in a new tab)
CWE-1321  (opens in a new tab)

How to fix?

Upgrade Echo:latest firefox-esr to version 91.9.1esr-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.

If an attacker was able to corrupt the methods of an Array object in JavaScript via prototype pollution, they could have achieved execution of attacker-controlled JavaScript code in a privileged context. This vulnerability affects Firefox ESR < 91.9.1, Firefox < 100.0.2, Firefox for Android < 100.3.0, and Thunderbird < 91.9.1.

CVSS Base Scores

version 3.1