CVE-2017-7793 : Security Advisory and Response

A use-after-free vulnerability in the Fetch API affecting Firefox, Firefox ESR, and Thunderbird.

Understanding CVE-2017-7793

A vulnerability in the Fetch API that could lead to a crash and potential exploitation.

What is CVE-2017-7793?

The Fetch API may experience a use-after-free vulnerability if the worker or associated window are released while still in use.
Versions affected include Firefox < 56, Firefox ESR < 52.4, and Thunderbird < 52.4.

The Impact of CVE-2017-7793

Exploitation of this vulnerability could potentially lead to a crash that can be exploited.

Technical Details of CVE-2017-7793

A vulnerability in the Fetch API that affects multiple Mozilla products.

Vulnerability Description

A use-after-free vulnerability can occur in the Fetch API when the worker or associated window are freed while still in use.
This could result in a potentially exploitable crash.

Affected Systems and Versions

Products affected: Firefox, Firefox ESR, Thunderbird
Versions affected: Firefox < 56, Firefox ESR < 52.4, Thunderbird < 52.4

Exploitation Mechanism

The vulnerability can be exploited if the worker or associated window are released while still in use.

Mitigation and Prevention

Steps to mitigate and prevent the CVE-2017-7793 vulnerability.

Immediate Steps to Take

Update affected products to versions equal to or greater than Firefox 56, Firefox ESR 52.4, and Thunderbird 52.4.
Monitor vendor advisories for patches and updates.

Long-Term Security Practices

Regularly update software to the latest versions.
Implement security best practices to prevent exploitation.

Patching and Updates

Apply patches provided by Mozilla for Firefox, Firefox ESR, and Thunderbird to address the vulnerability.