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TI-2026-51731 Aliases CVE-2026-73647GHSA-3r53-75j5-3g7j

Quasar Framework: Prototype pollution in Quasar extend() utility

Priority MEDIUM 58CWE-1321Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
High
Impact type
—
Confidentiality · integrity · availability
Low · Low · Low
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub.

Summary

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.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00387 33rd percentileScored 2026-11-07
Fix Fixed quasar (quasarframework): 2.22.0quasar (npm): 2.22.0

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
quasarframeworkquasarbefore 2.22.02.22.0Patch availableCNA
—quasar (npm)before 2.22.02.22.0Patch availableGHSA-3r53-75j5-3g7j
  • quasar Vendorquasarframework Affected before 2.22.0 Fixed in 2.22.0 Patch available CNA
  • quasar (npm) Vendor— Affected before 2.22.0 Fixed in 2.22.0 Patch available GHSA-3r53-75j5-3g7j

Remediation

  • Fix · CNA quasar (quasarframework) Fixed in 2.22.0
  • Fix · GHSA-3r53-75j5-3g7j quasar (npm) Fixed in 2.22.0 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-73647
  2. 2026-10-03 Alias added: GHSA-3r53-75j5-3g7j

References

Other 4

  • TI-2026-68624 Regex backtracking on User-Agent header stalls Quasar SSR servers CVSS 4.0HIGH 8.7
  • TI-2026-68626 Quasar SSR dev error page leaks environment secrets and enables XSS CVSS 4.0HIGH 7.1
  • TI-2026-68622 Cross-site scripting in Quasar Framework SSR meta tags CVSS 3.1CRITICAL 10.0
  • TI-2026-68621 Type confusion in quasarframework quasar CVSS 3.1LOW 3.1
  • TI-2026-68625 Quasar caches development TLS keys with lax file permissions CVSS 4.0HIGH 8.4
  • TI-2026-68627 Unsafe nonce interpolation in Quasar app-vite SSR and SSG output CVSS 4.0HIGH 8.3
See all 9 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences