CVE-2023-23598
MediumCVSS 6.5Exploitation Probability (EPSS)
Elevated risk50th percentile - higher than 50% of all known CVEs
Summary
Due to the Firefox GTK wrapper code's use of text/plain for drag data and GTK treating all text/plain MIMEs containing file URLs as being dragged, a website could arbitrarily read a file via a call to DataTransfer.setData. This vulnerability affects Firefox < 109, Firefox ESR < 102.7, and Thunderbird < 102.7.
Risk Assessment
This could allow a malicious website to read local files from the user's system, leading to leakage of sensitive information.
Recommendation
Update Firefox to version 109 or later, Firefox ESR to 102.7 or later, and Thunderbird to 102.7 or later.
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Original NVD description (English source)
Due to the Firefox GTK wrapper code's use of text/plain for drag data and GTK treating all text/plain MIMEs containing file URLs as being dragged a website could arbitrarily read a file via a call to `DataTransfer.setData`. This vulnerability affects Firefox < 109, Firefox ESR < 102.7, and Thunderbird < 102.7.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS