Vulnerabilities in pkg:golang/github.com/abhinavxd/libredesk

PACKAGE
Advisory Identifier: GHSA-wgm6-9rvv-3438
Advisory Summary

CVE-2026-26957 is a MODERATE libredesk has a ssrf vulnerability vulnerability (CWE-209: Generation of Error Message Containing Sensitive Information) affecting Withdrawn Advisory libraries in the Go ecosystem. The issue involves libredesk has a ssrf vulnerability in webhooks. Remediation is available by upgrading affected packages to version 1.0.2-0.20260215211005-727213631ce6.

2 Known Advisory Record(s)
Package Vulnerability Intelligence

pkg:golang/github.com/abhinavxd/libredesk

2 Known Advisory Record(s)

Vulnerability advisories affecting package pkg:golang/github.com/abhinavxd/libredesk. Select an advisory below to view technical details or fixes.

Advisory ID CVE / NVD Severity Summary
GHSA-wgm6-9rvv-3438 CVE-2026-26957 MODERATE Withdrawn Advisory: Libredesk has a SSRF Vulnerability in Webhooks
GHSA-wh6m-h6f4-rjf4 CVE-2025-68927 HIGH Libredesk has Improper Neutralization of HTML Tags in a Web Page

CVE-2026-26957 at a Glance

CVE Identifier CVE-2026-26957
GHSA Identifier GHSA-wgm6-9rvv-3438
Severity MODERATE
CVSS v3.1 Base Score N/A
CWE Classification CWE-209: Generation of Error Message Containing Sensitive Information
Affected Product Withdrawn Advisory
Package Ecosystem Go
Published Date
Last Updated

How to Fix CVE-2026-26957

To remediate this vulnerability, upgrade all affected Withdrawn Advisory dependencies to a patched release.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

github.com/abhinavxd/libredesk fixed: 1.0.2-0.20260215211005-727213631ce6
Upgrade github.com/abhinavxd/libredesk to 1.0.2-0.20260215211005-727213631ce6
Verify Direct and Transitive Dependencies

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

inspect dependencies for github.com/abhinavxd/libredesk

How to Check if You Are Affected

To determine whether your application is affected by CVE-2026-26957, inspect your project dependencies for Withdrawn Advisory:

inspect dependencies for github.com/abhinavxd/libredesk

Analyze the terminal output to locate any version of Withdrawn Advisory in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 1.0.2-0.20260215211005-727213631ce6), your application is affected.

Note: Verify declared build manifests and deployed runtime container environments.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-209: Generation of Error Message Containing Sensitive Information, where the product generates an error message that includes sensitive information about its environment, users, or associated data. In Withdrawn Advisory, 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

## Reconsidered - Working as designed. (Update 2026-05-28) Libredesk is a single-tenant, self-hosted application. Configuring outbound webhook URLs requires an admin-only permission that is not granted by default - the operator must explicitly assign it. Anyone holding this permission already has full administrative control over the application, and outbound HTTP to operator-chosen URLs is the documented purpose of the webhook feature. This is working as designed. A SECURITY.md documenting the threat model will be added to the repo shortly. ------------------------------------------------------------------------------------------------------------------------------ **Date:** 2025-12-07 **Vulnerability:** Server-Side Request Forgery (SSRF) **Severity:** Medium **Component:** Webhooks Module ## Executive Summary A critical security vulnerability exists in the LibreDesk Webhooks module that allows an authenticated "Application Admin" to compromise the underlying cloud infrastructure or internal corporate network where this service is being hosted. The application fails to validate destination URLs for webhooks. This allows an attacker to force the server to make HTTP requests to arbitrary internal destinations. ## Confirmed Attack Vectors ### 1. Internal Port Scanning (Network Mapping) Attackers can map the internal network by observing the difference between successful connections and connection errors. This works even if the response body is not returned. **Proof of Exploitation (from Server Logs):** * **Open Port (8890)**: The server connects successfully. ```text timestamp=... level=info message="webhook delivered successfully" ... status_code=200 ``` * **Closed Port (8891)**: The server fails to connect. ```text timestamp=... level=error message="webhook delivery failed" ... error="... connect: connection refused" ``` **Impact**: An attacker can identify running services (databases, caches, internal apps) on the local network (e.g., `localhost`, `192.168.x.x`). ### 2. Information Leakage (Error-Based) If the internal service returns a non-2xx response (e.g., 403 Forbidden, 404 Not Found, 500 Error), the application **logs the full response body**. **Proof of Exploitation (from Server Logs):** ```text timestamp=... level=error message="webhook delivery failed" ... response="{\"secret_key\": \"xxx123\", \"role\": \"admin\"}" ``` **Impact**: An attacker can extract sensitive data by targeting endpoints that return errors or by forcing errors on internal services. ## Technical Root Cause 1. **Missing Input Validation**: `cmd/webhooks.go` only checks if the URL is empty, not if it resolves to a private IP. 2. **Unrestricted HTTP Client**: `internal/webhook/webhook.go` uses a default `http.Client` that follows redirects and connects to any IP. 3. **Verbose Error Logging**: The application logs the full response body on failure, creating a side-channel for data exfiltration. ## Remediation Required To prevent this, the application must implement **Defense in Depth**: 1. **Input Validation**: Block URLs resolving to private IP ranges (RFC 1918) and Link-Local addresses. 2. **Safe HTTP Client**: Use a custom `http.Transport` that verifies the destination IP address *after* DNS resolution to prevent DNS rebinding attacks.

CVE-2026-26957 Affected Withdrawn Advisory Versions

1 component(s)
Fixed Versions:
1.0.2-0.20260215211005-727213631ce6
Product / Package Ecosystem Affected Versions Fixed Version
github.com/abhinavxd/libredesk
Go
< 1.0.2-0.20260215211005-727213631ce6
1.0.2-0.20260215211005-727213631ce6

References

Frequently Asked Questions

What is CVE-2026-26957?
CVE-2026-26957 is a security vulnerability in Withdrawn Advisory involving Libredesk has a SSRF Vulnerability in Webhooks under CWE-209: Generation of Error Message Containing Sensitive Information.
Which Withdrawn Advisory versions are affected?
Affected versions include releases prior to 1.0.2-0.20260215211005-727213631ce6 across affected packages: github.com/abhinavxd/libredesk.
What version fixes CVE-2026-26957?
Upgrading to 1.0.2-0.20260215211005-727213631ce6 (or the latest patched release for your respective branch) resolves the vulnerability.
Is github.com/abhinavxd/libredesk affected?
Yes, github.com/abhinavxd/libredesk is affected in releases prior to 1.0.2-0.20260215211005-727213631ce6. Upgrade your dependency to 1.0.2-0.20260215211005-727213631ce6 or later.
What CWE is associated with CVE-2026-26957?
CVE-2026-26957 is classified under CWE-209: Generation of Error Message Containing Sensitive Information (The product generates an error message that includes sensitive information about its environment, users, or associated data.).
How can I check Go dependencies for CVE-2026-26957?
Run the dependency tree command: 'inspect dependencies for github.com/abhinavxd/libredesk'. 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
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-wgm6-9rvv-3438",
  "modified" : "2026-06-09T14:28:34Z",
  "published" : "2026-02-18T00:56:30Z",
  "withdrawn" : "2026-06-09T14:28:34Z",
  "aliases" : [ "CVE-2026-26957" ],
  "summary" : "Withdrawn Advisory: Libredesk has a SSRF Vulnerability in Webhooks",
  "details" : "## Reconsidered -  Working as designed. (Update 2026-05-28)\n\nLibredesk is a single-tenant, self-hosted application. Configuring outbound webhook URLs requires an admin-only permission that is not granted by default - the operator must explicitly assign it.\n\nAnyone holding this permission already has full administrative control over the application, and outbound HTTP to operator-chosen URLs is the documented purpose of the webhook feature. This is working as designed.\n\nA SECURITY.md documenting the threat model will be added to the repo shortly.\n\n------------------------------------------------------------------------------------------------------------------------------\n\n**Date:** 2025-12-07\n**Vulnerability:** Server-Side Request Forgery (SSRF)\n**Severity:** Medium\n**Component:** Webhooks Module\n\n## Executive Summary\nA critical security vulnerability exists in the LibreDesk Webhooks module that allows an authenticated \"Application Admin\" to compromise the underlying cloud infrastructure or internal corporate network where this service is being hosted.\n\nThe application fails to validate destination URLs for webhooks. This allows an attacker to force the server to make HTTP requests to arbitrary internal destinations.\n\n## Confirmed Attack Vectors\n\n### 1. Internal Port Scanning (Network Mapping)\nAttackers can map the internal network by observing the difference between successful connections and connection errors. This works even if the response body is not returned.\n\n**Proof of Exploitation (from Server Logs):**\n*   **Open Port (8890)**: The server connects successfully.\n    ```text\n    timestamp=... level=info message=\"webhook delivered successfully\" ... status_code=200\n    ```\n*   **Closed Port (8891)**: The server fails to connect.\n    ```text\n    timestamp=... level=error message=\"webhook delivery failed\" ... error=\"... connect: connection refused\"\n    ```\n\n**Impact**: An attacker can identify running services (databases, caches, internal apps) on the local network (e.g., `localhost`, `192.168.x.x`).\n\n### 2. Information Leakage (Error-Based)\nIf the internal service returns a non-2xx response (e.g., 403 Forbidden, 404 Not Found, 500 Error), the application **logs the full response body**.\n\n**Proof of Exploitation (from Server Logs):**\n```text\ntimestamp=... level=error message=\"webhook delivery failed\" ... \nresponse=\"{\\\"secret_key\\\": \\\"xxx123\\\", \\\"role\\\": \\\"admin\\\"}\"\n```\n\n**Impact**: An attacker can extract sensitive data by targeting endpoints that return errors or by forcing errors on internal services.\n\n## Technical Root Cause\n1.  **Missing Input Validation**: `cmd/webhooks.go` only checks if the URL is empty, not if it resolves to a private IP.\n2.  **Unrestricted HTTP Client**: `internal/webhook/webhook.go` uses a default `http.Client` that follows redirects and connects to any IP.\n3.  **Verbose Error Logging**: The application logs the full response body on failure, creating a side-channel for data exfiltration.\n\n## Remediation Required\nTo prevent this, the application must implement **Defense in Depth**:\n\n1.  **Input Validation**: Block URLs resolving to private IP ranges (RFC 1918) and Link-Local addresses.\n2.  **Safe HTTP Client**: Use a custom `http.Transport` that verifies the destination IP address *after* DNS resolution to prevent DNS rebinding attacks.",
  "severity" : [ {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Go",
      "name" : "github.com/abhinavxd/libredesk"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "1.0.2-0.20260215211005-727213631ce6"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/abhinavxd/libredesk/security/advisories/GHSA-wgm6-9rvv-3438"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-26957"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/abhinavxd/libredesk/commit/727213631ce6a36bcb06f50ce542155e78f51316"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/abhinavxd/libredesk"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-209", "CWE-918" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-02-18T00:56:30Z",
    "nvd_published_at" : "2026-02-20T00:16:15Z"
  }
}