CVE-2026-86158

Summary

Missing authentication in the local .NET backend (Fiddler.WebUi) of Progress Software Fiddler Everywhere 8.0.2 allows a local unauthenticated attacker to mint OAuth tokens and read the machine-in-the-middle root certificate through an unauthenticated localhost HTTP and SignalR RPC channel.

Affected Software

Weaknesses

• CWE-306: CWE-306: Missing Authentication for Critical Function

ADP Enrichment

CISA ADP Vulnrichment

• SSVC:
• Exploitation: none
  • Automatable: no
  • Technical Impact: total

References

• https://www.telerik.com/fiddler/fiddler-everywhere/documentation/knowledge-base/kb-security-missing-authentication-for-critical-function-cve-2026-86158

• ←Previous
• Next→