40 lines
886 B
Plaintext
40 lines
886 B
Plaintext
== How to fix it in Node.js
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=== Code examples
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The following code is vulnerable to arbitrary code execution because it dynamically
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runs JavaScript code built from untrusted data.
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==== Noncompliant code example
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[source,javascript,diff-id=1,diff-type=noncompliant]
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----
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function (req, res) {
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let operation = req.query.operation
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eval(`product_${operation}()`) // Noncompliant
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res.send("OK")
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}
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----
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==== Compliant solution
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[source,javascript,diff-id=1,diff-type=compliant]
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----
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const allowed = ["add", "remove", "update"]
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let operationId = req.query.operationId
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const operation = allowed[operationId]
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eval(`product_${operation}()`)
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res.send("OK")
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----
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=== How does this work?
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include::../../common/fix/introduction.adoc[]
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include::../../common/fix/parameters.adoc[]
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include::../../common/fix/allowlist.adoc[]
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The example compliant code uses such a binding approach.
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