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| Package Name | Ecosystem | Vulnerable Versions | First Patched Version |
|---|---|---|---|
| @apeleghq/asn1-der | npm | < 1.0.4 | 1.0.4 |
Miggo AIRoot Cause AnalysisThe analysis focused on the provided commit b2bc9032cbe19755d234a27d79e47a7e52993af8 and the vulnerability description.
The description highlighted two main issues: an infinite loop in numBitLen for specific input ranges, and incorrect DER encoding of numbers.
The commit patch directly modifies two functions in src/lib/encode2sComplement.ts: numBitLen and encode2sComplement.
numBitLen: The patch alters the loop condition and arithmetic (x /= 2 to Math.floor(x/2) and while (x >= 4294967296) to while (x >>> 0 !== x)) to prevent the infinite loop described. This function is therefore identified as vulnerable in its pre-patch state.encode2sComplement: This function, which handles the actual encoding, received several changes. These include modifications to loop conditions for handling multi-byte numbers and, crucially, changing a signed right shift (>>=) to an unsigned right shift (>>>=). These changes address the 'incorrect value representation' mentioned in the advisory. This function processed the input and contained encoding flaws.The advisory mentions Asn1Integer as the class where inputs are provided. While Asn1Integer is the likely higher-level consumer of these vulnerable functions, it is not directly modified in the provided patch. Therefore, based on the instruction to focus on functions explicitly visible in the patch, numBitLen and encode2sComplement are the identified vulnerable functions whose flaws were fixed by the commit.