fix(provider-utils): prevent unicode escape bypass in secureJsonParse#13079
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fix(provider-utils): prevent unicode escape bypass in secureJsonParse#13079
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Update regex patterns to detect unicode-escaped variants of __proto__ and constructor keys, matching the upstream fix in fastify/secure-json-parse. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
…ureJsonParse Align with upstream fastify/secure-json-parse by guarding against node.constructor being null or a non-object before calling hasOwnProperty on it. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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…#13079) ## Summary - Update `secureJsonParse` regex patterns to detect unicode-escaped variants of `__proto__` and `constructor` keys, preventing prototype pollution bypass - Aligns with the upstream fix in [fastify/secure-json-parse](https://github.com/fastify/secure-json-parse) - Add regression tests for partial and fully unicode-escaped key variants ## Security Resolves VULN-774. The previous regex fast-path only matched literal `"__proto__"` and `"constructor"` strings. Unicode escapes (e.g., `\u005f\u005fproto__`) bypassed the regex gate, skipping the `filter()` safety check, while `JSON.parse` still normalized them into dangerous keys. --------- Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>
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✅ Backport PR created: #13083 |
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Summary
secureJsonParseregex patterns to detect unicode-escaped variants of__proto__andconstructorkeys, preventing prototype pollution bypassSecurity
Resolves VULN-774. The previous regex fast-path only matched literal
"__proto__"and"constructor"strings. Unicode escapes (e.g.,\u005f\u005fproto__) bypassed the regex gate, skipping thefilter()safety check, whileJSON.parsestill normalized them into dangerous keys.Test plan
secureJsonParsetests pass__proto__is rejectedconstructoris rejected