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TI-2026-67614 Aliases CVE-2026-77805GHSA-mpj7-wp32-q53h

Weak helper tool signature checks in Telerik Fiddler Classic

Priority LOW 35CWE-347Published · Updated

Key facts

Attack vector
Local
Privileges required
Low
User interaction
Required
Attack complexity
Low
Impact type
Security bypass
Confidentiality · integrity · availability
High · High · None
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-347.

Summary

Progress Telerik Fiddler Classic for Windows from 1.0.0 before 6.0.20262.10021 checks only the publisher name in the Authenticode signature of external helper tools before running them, not that each file is the shipped executable (CWE-347). A local user with low privileges can swap a helper for another validly signed binary from an allowed publisher, which then runs with Administrator privileges for tools that request elevation after a user approves the prompt.

Written with Claude Haiku 5.5 from the sources below · 2026-10-29

Description from the CNA

In Progress® Telerik® Fiddler® Classic for Windows, versions prior to v6.0.20262.10021, the integrity check applied to the external helper tools launched by the application is insufficient. Before executing a helper tool, the application only verifies that the file carries a valid Authenticode signature whose certificate subject name matches a broad allow list of publisher name fragments, rather than verifying that the file is the specific executable shipped with that version of the product. A local threat actor with low privileges who replaces one of these helper executables with any other validly signed binary from an allow-listed publisher can cause the substituted binary to be executed by the application, including with Administrator privileges for the tools that request elevation, resulting in privilege escalation and execution of unintended code. Successful exploitation requires the user to launch the affected external tool and to approve the elevation prompt without noticing that it refers to a different executable.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00068 0th percentileScored 2026-11-07
Fix Fixed Progress® Telerik® Fiddler® Classic (Progress Software): 6.0.20262.10021

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

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

Affected products

VendorProductAffected versionsFixed inStatusSource
ProgressProgress® Telerik® Fiddler® Classic1.0.0 to before 6.0.20262.100216.0.20262.10021Patch availableCNA
  • Progress® Telerik® Fiddler® Classic VendorProgress Affected 1.0.0 to before 6.0.20262.10021 Fixed in 6.0.20262.10021 Patch available CNA

Remediation

Upgrade Progress Telerik Fiddler Classic to version 6.0.20262.10021 or later.

Written with Claude Haiku 5.5 from the sources below · 2026-10-29

  • Fix · CNA Progress® Telerik® Fiddler® Classic (Progress Software) Fixed in 6.0.20262.10021

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Release ·

    Progress® Telerik® Fiddler® Classic 6.0.20262.10021

    4 records Highest priority Priority LOW 4 LOW

    Other records, highest priority first

    • TI-2026-67613 Race condition in Progress Telerik Fiddler Classic certificate installationPriority LOW 30
    • TI-2026-67611 HTTP request smuggling in Progress Telerik Fiddler ClassicPriority LOW 29
    • TI-2026-67612 Telerik Fiddler Classic front-end desynchronization enables request smugglingPriority LOW 16
    Show all 4 records →

Timeline

  1. 2026-10-05 Threatist record created from CVE-2026-77805
  2. 2026-10-05 Alias added: GHSA-mpj7-wp32-q53h
  3. 2026-10-05 CISA SSVC decision points changed
  4. 2026-10-05 Priority changed: MEDIUM → LOW

References

Advisory 1

  • TI-2026-07083 Command injection in Progress LoadMaster KEVCVSS 3.1CRITICAL 9.8
  • TI-2024-06182 WhatsUp Gold HasErrors SQL Injection Authentication Bypass Vulnerability KEVCVSS 3.1CRITICAL 9.8
  • TI-2024-04541 WhatsUp Gold GetFileWithoutZip Directory Traversal Remote Code Execution Vulnerability KEVCVSS 3.1CRITICAL 9.8
  • TI-2024-04060 Registration Authentication Bypass Vulnerability KEVCVSS 3.1CRITICAL 9.8
  • TI-2024-01127 LoadMaster Pre-Authenticated OS Command Injection KEVCVSS 3.1CRITICAL 10.0
  • TI-2023-20934 WS_FTP Server Ad Hoc Transfer Module .NET Deserialization Vulnerability KEVCVSS 3.1CRITICAL 10.0
See all 436 →

Sources

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