CVE-2026-16633: PDF.js: Arbitrary JavaScript execution upon opening a malicious PDF

August 6, 2026

If PDF.js is used to load a malicious PDF, and PDF.js is configured with enableScripting set to true (which is the default value) and no CSP for disallowing script-src, unrestricted attacker-controlled JavaScript will be executed in the context of the hosting domain.

References

bugzilla.mozilla.org/show_bug.cgi?id=2055885
github.com/advisories/GHSA-hq66-cqwq-w95j
github.com/mozilla/pdf.js/security/advisories/GHSA-hq66-cqwq-w95j
nvd.nist.gov/vuln/detail/CVE-2026-16633

Code Behaviors & Features

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