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CVE-2023-30533 is a prototype pollution vulnerability in SheetJS Community Edition affecting versions before 0.19.3. The issue can be triggered by processing a crafted file, allowing attacker-controlled data to modify JavaScript object prototypes. Versions 0.19.2 and earlier are affected, while 0.19.3 and later are not affected.
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1 valid exploit after Mallory filtered fakes, detection scripts, and README-only repos (1 hidden).
This repository is a proof-of-concept (POC) exploit for CVE-2023-30533, a prototype pollution vulnerability in the SheetJS 'xlsx' library (Community Edition) up to version 0.19.2. The repository contains a single JavaScript exploit script ('index.js') that loads a malicious XLSX file ('threaded_comment_bad.xlsx', not included in the file listing but referenced in the code) and parses it using the vulnerable 'xlsx' library. The script demonstrates the state of the Object prototype before and after parsing the file, showing that prototype pollution has occurred. The exploit does not provide a weaponized payload but clearly demonstrates the vulnerability's impact. The repository structure is minimal, with standard Node.js project files and dependencies, and the main exploit logic is contained in 'index.js'. No network endpoints or remote attack vectors are present; the attack is local and requires the attacker to supply a crafted XLSX file to an application using the vulnerable library.
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2 sources tracked across advisories and community write-ups. News coverage will land here when it surfaces.
No news coverage yet. Advisories and community discussion only.
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