CVE-2025-57820
HIGHCVSS Vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Lifecycle Timeline
3Description
Svelte devalue is a utility library. Prior to version 5.3.2, a string passed to devalue.parse could represent an object with a __proto__ property and devalue.parse does not check that an index is numeric. This could result in assigning prototypes to objects and properties, leading to prototype pollution. This issue has been fixed in version 5.3.2
Analysis
Svelte devalue is a utility library. Rated high severity (CVSS 7.9), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Technical Context
This vulnerability is classified as Improperly Controlled Modification of Object Prototype Attributes (Prototype Pollution) (CWE-1321), which allows attackers to modify object prototypes to inject properties affecting application logic. Svelte devalue is a utility library. Prior to version 5.3.2, a string passed to devalue.parse could represent an object with a __proto__ property and devalue.parse does not check that an index is numeric. This could result in assigning prototypes to objects and properties, leading to prototype pollution. This issue has been fixed in version 5.3.2 Version information: version 5.3.2.
Affected Products
See vendor advisory for affected versions.
Remediation
No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Freeze prototypes, validate object keys, avoid recursive merging of untrusted data.
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External POC / Exploit Code
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