Svelte devalue is a JavaScript library that serializes values into strings when JSON.stringify isn't sufficient for the job. Prior to 5.9.2, devalue.parse does not reject out-of-bounds indices that are greater than or equal to values.length in src/parse.js. A specially crafted untrusted payload can make the parser alternate between array representations, producing quadratic work as the payload grows and causing denial of service in applications that parse untrusted devalue data.
This issue is fixed in version 5.9.2.
Attack Parameters
Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Privileges Required
None
No privileges needed
User Interaction
None
No user interaction needed
Impact Assessment
Confidentiality
None
No data leak
Integrity
None
No data modification
Availability
Low
Partial disruption
CVSS Vector v3.1
Weakness Type (CWE)
References 3
https://github.com/sveltejs/devalue/commit/8b2a4562c446d7c36d9d629778079a5fae42…
security-advisories@github.com
https://github.com/sveltejs/devalue/releases/tag/v5.9.2
security-advisories@github.com
https://github.com/sveltejs/devalue/security/advisories/GHSA-9rgm-9g3h-6x36
security-advisories@github.com