CVE-2026-104183 (GCVE-0-2026-104183)

Vulnerability from cvelistv5 – Published: 2026-10-01 20:17 – Updated: 2026-10-01 20:30
VLAI
Title
stream-json: Prototype pollution: Assembler writes this.current[this.key] on plain objects
Summary
stream-json is a micro-library of stream components for processing JSON and JSONC with a minimal memory footprint. Prior to 3.6.0, Assembler materializes object properties with plain assignment, so an input key named __proto__ invokes the inherited setter and causes parsed object prototype replacement instead of creating an own data property. Applications that make authorization or feature decisions from inherited values can therefore consume attacker-controlled properties, and a null prototype can disrupt code that expects Object.prototype methods. The researcher treats parsing untrusted JSON as part of the project contract, while the maintainer states that documented inputs are locally owned dumps, exports, or logs and characterizes the attack vector as local. The global Object.prototype is not polluted. This issue is fixed in version 3.6.0.
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-10-01 20:29 UTC
CWE
  • CWE-1321 - Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution')
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7771 records in the last 180 days details
Impacted products
Vendor Product Version CPE status
uhop stream-json Affected: < 3.6.0
guessed Create a notification for this product.
Show details on NVD website

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