concat

typescript · standard library · Array
summaryDerived from model facts
RoleSummary
WeaknessNot mapped
WatchesArgument[0] -> ReturnValue
Kindconcat
Confidencehigh
Corroboration2

Summary boundary: Concatenation joins values before a later operation interprets the result.

Argument map · what each slot does

The pack does not provide a callable signature for this record; the watched access path is shown directly.

ArgAccess pathPurposeWatched
Argument[0]Argument[0]The access path Atropos marks for this model.▲ summary
The weakness
No CWE mapping in this fact

The model classifies the behavior as concat; no CWE relationship is attached to this record.

What goes wrong
Attacker's-eye view · concat

An attacker-controlled fragment changes the meaning of the assembled string at its next boundary.

// modeled boundary: Argument[0] -> ReturnValue concat(attacker_influenced_value);
To decide if this call is a bug, check
1Locate the next interpreter or parser.
2Keep structure separate from values.
3Validate the resulting domain.
These checks require the surrounding codebase. The model names the boundary; it does not decide reachability or prove that a guard dominates every path.
Is this a bug in your code?Atropos stops here — by design

Atropos identifies Argument[0] -> ReturnValue as a concat summary. It cannot see whether untrusted data reaches this call in your repository.

Lachesis is the codebase-level step: it traces reachability and guards for this symbol.

Check this symbol in Lachesis
The family · concat

Across languages

No cross-language match.

What neutralizes it

No sanitizer of this kind is modeled.

Model facts · verbatim from the pack
RoleKindAccess pathModel IDConfidence
summaryconcatArgument[0] -> ReturnValuetypescript.array.concat.a0-rethigh · corrob. 2
summarytransformReceiver -> ReturnValuetypescript.array.concat.recv-rethigh · corrob. 2