CVE-2026-77805: Software Security Vulnerability Vulnerability

HIGH
Advisory Identifier: GHSA-mpj7-wp32-q53h
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CVSS 7.9
CWE-347
Published
Advisory Summary

CVE-2026-77805 is a HIGH (CVSS 7.9) security vulnerability vulnerability (CWE-347: Improper Verification of Cryptographic Signature) affecting Software libraries in the Maven ecosystem. The weakness occurs when the product does not verify, or incorrectly verifies, the cryptographic signature for data.. Remediation is available in the latest vendor maintenance releases.

CVE-2026-77805 at a Glance

CVE Identifier CVE-2026-77805
GHSA Identifier GHSA-mpj7-wp32-q53h
Severity HIGH
CVSS v3.1 Base Score 7.9
CWE Classification CWE-347: Improper Verification of Cryptographic Signature
Affected Product Software
Package Ecosystem Maven
Published Date
Last Updated

Security Impact

CVSS: 7.9

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N).

Attack Vector Local (AV:L)
Attack Complexity Low (AC:L)
Privileges Required Low (PR:L)
User Interaction Required (UI:R)
Scope Changed (S:C)
Confidentiality High (C:H)
Integrity High (I:H)
Availability None (A:N)

How to Fix CVE-2026-77805

To remediate this vulnerability, upgrade all affected Software dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

mvn dependency:tree

How to Check if You Are Affected

To determine whether your Java application is affected by CVE-2026-77805, inspect your build dependencies using the Maven Dependency Plugin:

mvn dependency:tree

Analyze the terminal output to locate any version of Software in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than the patched release), your application is affected.

Note: The mvn dependency:tree command inspects the resolved dependency graph declared in your project's POM files; it does not perform automated security scanning or inspect runtime dynamic classpaths. Always verify runtime container classpaths and shaded JARs.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-347: Improper Verification of Cryptographic Signature, where the product does not verify, or incorrectly verifies, the cryptographic signature for data. In Software, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

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.

References

NVD — CVE-2026-77805 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-77805
Software Security Information SECURITY
https://docs.telerik.com/fiddler/knowledge-base/kb-security-weak-executable-signature-verification-cve-2026-77805

Frequently Asked Questions

What is CVE-2026-77805?
CVE-2026-77805 is a security vulnerability in Software classified as a security vulnerability vulnerability under CWE-347: Improper Verification of Cryptographic Signature.
Which Software versions are affected?
Affected versions include releases prior to current release patches.
What version fixes CVE-2026-77805?
Upgrading to current release patches (or the latest patched release for your respective branch) resolves the vulnerability.
What is the CVSS score of CVE-2026-77805?
CVE-2026-77805 has a CVSS v3.1 base score of 7.9 (HIGH) with vector string CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N.
What CWE is associated with CVE-2026-77805?
CVE-2026-77805 is classified under CWE-347: Improper Verification of Cryptographic Signature (The product does not verify, or incorrectly verifies, the cryptographic signature for data.).
How can I check Maven dependencies for CVE-2026-77805?
Run the dependency tree command: 'mvn dependency:tree'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-mpj7-wp32-q53h",
  "modified" : "2026-10-05T15:32:22Z",
  "published" : "2026-10-05T15:32:22Z",
  "aliases" : [ "CVE-2026-77805" ],
  "details" : "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.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N"
  } ],
  "affected" : [ ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-77805"
  }, {
    "type" : "WEB",
    "url" : "https://docs.telerik.com/fiddler/knowledge-base/kb-security-weak-executable-signature-verification-cve-2026-77805"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-347" ],
    "severity" : "HIGH",
    "github_reviewed" : false,
    "github_reviewed_at" : null,
    "nvd_published_at" : "2026-10-05T13:16:54Z"
  }
}