> CVE-2026-61534 [CRITICAL]

« BACK_TO_HOME
PUBLISHED
2026-09-14 16:17
MODIFIED
2026-09-14 16:17
CVSS_SCORE V3
9.1
EPSS (Prob. Exploit)
0.84%
Top 42.9%
DATA SOURCES:
NVD đź”— 2026-09-14 CWE MITRE đź”— 2026-10-01 FIRST EPSS đź”— 2026-10-18 GITHUB đź”— 2026-10-15 OSV đź”— 2026-10-26

> DESCRIPTION

Yayson is a library for serializing and reading JSON API data in JavaScript. Prior to 4.3.0, Store and LegacyStore use attacker-controlled JSON:API type, id, and relationship names as keys in plain-object lookup tables in src/yayson/store.ts and src/yayson/legacy-store.ts. A document whose type is __proto__ causes model-cache writes to modify Object.prototype, with the attacker controlling the polluted property name through id and its value through attributes. The malicious type can also be supplied by an included resource, and LegacyStore is reachable when a configured types mapping resolves to __proto__. Unsafe relationship names including __proto__, constructor, and prototype provide additional document-derived member paths. The resulting process-wide prototype pollution can cause denial of service and logic corruption; authorization bypass or code execution depends on suitable gadgets in the consuming application. This issue is fixed in version 4.3.0.

> AFFECTED_PRODUCTS

ℹ️ Aucun produit affecté n'a encore été publié par NVD pour cette CVE.

> CVSS V3 METRICS

CVSS_VECTOR
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H
EXPLOITABILITY
3.9
IMPACT
5.2

> MÉTRIQUES CVSS DÉTAILLÉES

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H
Métrique Valeur Interprétation
AV (Vecteur d'Attaque)
Attack Vector
Network (N)
Exploit possible à distance via réseau (HTTP, API, etc.)
AC (Complexité d'Attaque)
Attack Complexity
Low (L)
Peu de conditions requises pour exploiter
PR (Privilèges Requis)
Privileges Required
None (N)
Aucune authentification requise
UI (Interaction Utilisateur)
User Interaction
None (N)
Aucune interaction utilisateur nécessaire
S (Périmètre)
Scope
Unchanged (U)
Impact reste dans le périmètre du composant compromis
C (Impact Confidentialité)
Confidentiality Impact
None (N)
Aucune divulgation d'informations
I (Impact Intégrité)
Integrity Impact
High (H)
Modification totale des données possible
A (Impact Disponibilité)
Availability Impact
High (H)
Interruption totale du service possible

> RÉSUMÉ DES IMPACTS

Confidentialité
None
Aucune divulgation d'informations
Intégrité
High
Modification totale des données possible
Disponibilité
High
Interruption totale du service possible

> WEAKNESSES

CWE-1321

> CWE DETAILED DESCRIPTIONS

CWE-1321: Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution') - The product receives input from an upstream component that specifies attributes that are to be initialized or updated in an object, but it does not properly control modifications of attributes of the object prototype.

> GITHUB SECURITY ADVISORY

GHSA-325j-mg25-8q58 CRITICAL

yayson: Prototype pollution in Store/LegacyStore deserialization

AFFECTED PACKAGES:
NPM / yayson
<= 4.2.0
Fixed in: 4.3.0

> OSV (GOOGLE OPEN SOURCE VULNERABILITIES)

Yayson: Prototype pollution in the Store/LegacyStore deserialization

AFFECTED PACKAGES:
Unknown / Unknown
19 versions affected
ALIASES:
GHSA-325j-mg25-8q58

> HISTORIQUE DES MODIFICATIONS

Première apparition
14/09/2026 16:17
Source: NVD
📊 ENRICHISSEMENT 01/10/2026 06:01
CWE
Champ modifié: Description CWE
Ancienne valeur:
N/A
Nouvelle valeur:
CWE-1321: Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution') - The product receives input from an upstream component that specifies attributes that are to be ini...
Total des modifications: 1 Dernière mise à jour: 3 weeks ago

> REFERENCES

https://github.com/confetti/yayson/commit/e460162d5a3ebac86424bead7424957c36f8df...
https://github.com/confetti/yayson/pull/111
https://github.com/confetti/yayson/releases/tag/v4.3.0
https://github.com/confetti/yayson/security/advisories/GHSA-325j-mg25-8q58
« BACK_TO_HOME