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TypeError: invalid 'instanceof' operand KeyObject

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#950 13 comments 2 reactions 0 assignees View on GitHub

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Assessment

Difficulty
3/5
Estimated time
1-2 days
Newbie friendliness
25/100
Issue type
Bug
Clarity
Needs clarification
Activity status
Stale

Research direction

Start by reproducing the supplied verify(token, jwtSecret) call in the stated TypeScript, jsonwebtoken, and Next.js environment, then inspect the jsonwebtoken verify entry point involved in the error. Done means the reproduction no longer throws the invalid instanceof KeyObject TypeError, with the behavior covered by a regression test.

Written by the indexing model from the issue text.

Description

Description

TypeError: invalid 'instanceof' operand KeyObject

Reproduction
import { verify } from 'jsonwebtoken';

const jwtSecret = 'fooSecret';

export const JwtDecode = (token: string): Nullable<IJwtSignModel> => {
  if (!token) return null;
  return verify(token, jwtSecret) as IJwtSignModel;
};

// *Unhandled Runtime Error
TypeError: invalid 'instanceof' operand KeyObject

Environment

Please provide the following:
typescript: 5.2.2
jsonwebtoken: 9.0.2
@types/jsonwebtoken: 9.0.5 //tried with 9.0.2 too
Next js 14

Dominant language
JavaScript
Stars
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Forks
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PR merge metrics
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