CVE-2026-86157: Exposure of Privileged IPC Functionality in Progress Telerik Fiddler Everywhere

Severity: medium (CVSS 5.6 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.1% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-09-29 · updated 2026-09-30
Weakness: CWE-749

Description

Exposure of privileged IPC functionality in Progress Telerik Fiddler Everywhere before version 8.2.0 allows a local, low-privileged attacker who can modify application launch parameters and persuade a user to start the application to replace the application UI or settings with attacker-controlled content. Successful exploitation could result in disclosure of OAuth authentication tokens, execution of locally accessible programs, or unauthorized modification of application-generated configuration files.

Affected products

Progress Software Progress® Telerik® Fiddler® Everywhere: from 1.0.0 before 8.2.0 — fixed in 8.2.0

How to fix

Upgrade to a fixed version: Progress Software Progress® Telerik® Fiddler® Everywhere 8.2.0. Check the vendor advisory for mitigations.

References

https://www.telerik.com/fiddler/fiddler-everywhere/documentation/knowledge-base/kb-security-exposed-dangerous-method-or-function-cve-2026-86157

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