CVE-2026-73647: CWE-1321: Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution') in quasarframework quasar
Quasar Framework is a framework for building high-performance Vue.js user interfaces. Prior to 2.22.0, the public extend() utility in ui/src/utils/extend/extend.js recursively copied attacker-controlled object keys during extend(true, target, source) deep merges without rejecting an own __proto__ property. The merge could descend into the prototype object and write attacker-controlled properties to Object.prototype in the same JavaScript process. Applications that passed user-controlled or partially user-controlled objects to extend() could experience logic bypass, unsafe default-option injection, denial of service, or other application-specific impact when polluted properties were later consumed. This issue is fixed in version 2.22.0.
AI Analysis
Technical Summary
Quasar Framework versions before 2.22.0 contain a prototype pollution vulnerability in the public extend() utility located in ui/src/utils/extend/extend.js. The function recursively copies object keys during deep merges (extend(true, target, source)) but does not reject the __proto__ property. This enables an attacker to write properties to Object.prototype within the same JavaScript process. Applications passing user-controlled or partially user-controlled objects to extend() are vulnerable to logic bypass, unsafe default-option injection, denial of service, or other impacts when polluted properties are used later. The issue is resolved in version 2.22.0.
Potential Impact
An attacker able to supply objects to the extend() function can modify the Object.prototype, leading to potential logic bypass, injection of unsafe default options, denial of service, or other application-specific impacts. The CVSS score of 5.6 (medium severity) reflects the network attack vector with high attack complexity and no privileges or user interaction required, impacting confidentiality, integrity, and availability at a low level.
Mitigation Recommendations
Upgrade Quasar Framework to version 2.22.0 or later, where this prototype pollution vulnerability is fixed. No official patch or temporary fix is indicated beyond upgrading. Applications should avoid passing user-controlled or partially user-controlled objects to the extend() function until upgraded.
CVE-2026-73647: CWE-1321: Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution') in quasarframework quasar
Description
Quasar Framework is a framework for building high-performance Vue.js user interfaces. Prior to 2.22.0, the public extend() utility in ui/src/utils/extend/extend.js recursively copied attacker-controlled object keys during extend(true, target, source) deep merges without rejecting an own __proto__ property. The merge could descend into the prototype object and write attacker-controlled properties to Object.prototype in the same JavaScript process. Applications that passed user-controlled or partially user-controlled objects to extend() could experience logic bypass, unsafe default-option injection, denial of service, or other application-specific impact when polluted properties were later consumed. This issue is fixed in version 2.22.0.
CVSS v3.1
Score 5.6medium
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
Quasar Framework versions before 2.22.0 contain a prototype pollution vulnerability in the public extend() utility located in ui/src/utils/extend/extend.js. The function recursively copies object keys during deep merges (extend(true, target, source)) but does not reject the __proto__ property. This enables an attacker to write properties to Object.prototype within the same JavaScript process. Applications passing user-controlled or partially user-controlled objects to extend() are vulnerable to logic bypass, unsafe default-option injection, denial of service, or other impacts when polluted properties are used later. The issue is resolved in version 2.22.0.
Potential Impact
An attacker able to supply objects to the extend() function can modify the Object.prototype, leading to potential logic bypass, injection of unsafe default options, denial of service, or other application-specific impacts. The CVSS score of 5.6 (medium severity) reflects the network attack vector with high attack complexity and no privileges or user interaction required, impacting confidentiality, integrity, and availability at a low level.
Mitigation Recommendations
Upgrade Quasar Framework to version 2.22.0 or later, where this prototype pollution vulnerability is fixed. No official patch or temporary fix is indicated beyond upgrading. Applications should avoid passing user-controlled or partially user-controlled objects to the extend() function until upgraded.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-08-13T14:04:09.604Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a7e08efbf8831d5399b79ab
Added to database: 08/13/2026, 18:11:59 UTC
Last enriched: 08/13/2026, 18:27:32 UTC
Last updated: 08/13/2026, 22:03:39 UTC
Views: 7
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