CVE-2025-57820
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
CVSS
- Version: 4.0
- 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
- Base score: 7.9
Exploitation probability (EPSS)
- Probability of exploitation in the next 30 days: 0.37%
- Percentile among all scored CVEs: 29
- Score date: 10/6/2026
EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).
🎯 ATT&CK techniques
How this vulnerability is exploited and what the attacker gains, in MITRE ATT&CK terms.
- Exploitation
T1190Exploit Public-Facing Applicationinitial access75 % - Primary impact
T1059.007JavaScriptexecution65 % - Secondary impact
T1565Data Manipulationimpact60 %
Aplicación web expuesta (Svelte devalue) vulnerable a inyección de prototype pollution mediante entrada no validada (AV:N/PR:N/UI:N); permite ejecución JavaScript y manipulación de datos en cliente.
Inferred by our analysis agent from the official description, CVSS vector and CWE, and checked by a supervisor. May contain errors.
🛡️ ATT&CK mitigations that cover these techniques
Affected technologies (1)
⚠ AI-inferred from the description — NVD hasn't analyzed this CVE yet, these aren't verified CPEs.
CWEs
- CWE-1321
References
Raw JSON (NVD)
Show
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"lastModified": "2026-06-17T09:43:29.903",
"sourceIdentifier": "security-advisories@github.com"
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