Grammarly Plugin Authentication Vulnerability

A vulnerability in the popular Grammarly spell-checking extension for Chrome and Firefox may allow a remote attacker to access user information.

Threat ID:: CC-2046
Category:
Threat Severity:: Low
Threat Vector:
Published:: 15 February 2018 12:00 AM

Report a cyber attack: call 0300 303 5222 or email [email protected]

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Summary

A vulnerability in the popular Grammarly spell-checking extension for Chrome and Firefox may allow a remote attacker to access user information.

Threat details

Disclosed in February 2017, the vulnerability exposes the authentication tokens used by Grammarly to any website the user visits. Using four lines of JavaScript, an attacker is able to access a user's account information, logs, documents and typing history.

Remediation steps

Type	Step
	Grammarly have confirmed the vulnerability has been patched in the latest version of their plugin. The extension should update automatically but can be forced to update if it has not.

Last edited: 17 February 2020 12:44 pm