🔐 CVE Alert

CVE-2026-86158

HIGH 7.7

Missing Authentication in the local .NET backend of Progress Telerik Fiddler Everywhere

CVSS Score
7.7
EPSS Score
0.0%
EPSS Percentile
0th

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.

CWE CWE-306
Vendor progress software
Product progress® telerik® fiddler® everywhere
Published Sep 29, 2026
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CVSS v3 Breakdown

CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Attack Vector
Local
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
None

Affected Versions

Progress Software / Progress® Telerik® Fiddler® Everywhere
1.0.0 < 8.2.0

References

NVD ↗ CVE.org ↗ EPSS Data ↗
telerik.com: https://www.telerik.com/fiddler/fiddler-everywhere/documentation/knowledge-base/kb-security-exposed-dangerous-method-or-function-cve-2026-aaaaa

Credits

whizarre