CVE-2026-86158Missing Authentication in the local .NET backend of Progress Telerik Fiddler Everywhere
Updated under an hour ago ()
Does this affect you?
It affects Progress Software Progress® Telerik® Fiddler® Everywhere. Add what you run to find out whether that includes you.
EPSS puts the chance of exploitation in the next 30 days at 0.09%, higher than 0% of scored CVEs.
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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.
- CVSS
- 7.7 HIGH (v3.1, CNA)CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
- Weakness (CWE)
- CWE-306
- Known exploited
- Not in CISA's KEV catalog
- EPSS (exploitation in the next 30 days)
- 0.09% (percentile 0)
- Assigned by
- ProgressSoftware
- NVD analysis
- Awaiting Analysis
- Record last updated
- Sep 30, 2026
- First seen by InfoSec Signals
- Oct 9, 2026
Affected products
Progress Software Progress® Telerik® Fiddler® Everywhere progress_software:progress_telerik_fiddler_everywhere (from the name) | from 1.0.0 before 8.2.0 | CNA record |
References
- https://www.telerik.com/fiddler/fiddler-everywhere/documentation/knowledge-base/kb-security-missing-authentication-for-critical-function-cve-2026-86158vendor-advisory
The CVE record on cve.org NVD's entry
The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.