CVE-2026-55466: Snipe/snipe it Cross-Site Scripting Vulnerability

MODERATE
Advisory Identifier: GHSA-jhph-5q74-pmfx
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CVSS 8.7
CWE-79
Published
Advisory Summary

CVE-2026-55466 is a MODERATE (CVSS 8.7) cross-site scripting vulnerability (CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')) affecting Snipe/snipe it libraries in the Packagist ecosystem. The issue involves snipe-it vulnerable to stored xss via inline-served attachment. Remediation is available by upgrading affected packages to version 8.6.2.

CVE-2026-55466 at a Glance

CVE Identifier CVE-2026-55466
GHSA Identifier GHSA-jhph-5q74-pmfx
Severity MODERATE
CVSS v3.1 Base Score 8.7
CWE Classification CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Affected Product Snipe/snipe it
Package Ecosystem Packagist
Published Date
Last Updated

Security Impact

CVSS: 8.7

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

Attack Vector Network (AV:N)
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-2026-55466

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

snipe/snipe-it fixed: 8.6.2 
Upgrade snipe/snipe-it to 8.6.2
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 snipe/snipe-it

How to Check if You Are Affected

To determine whether your application is affected by CVE-2026-55466, inspect your project dependencies for Snipe/snipe it:

inspect dependencies for snipe/snipe-it

Analyze the terminal output to locate any version of Snipe/snipe it in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 8.6.2), 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-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting'), where the product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. In Snipe/snipe it, 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

### Impact A low-privilege user can store an active-content payload as an asset attachment and have it served inline, same-origin, with an active Content-Type, achieving stored XSS. The application sanitizes uploads only when PHP finfo detects image/svg+xml. By submitting an XHTML document whose finfo MIME is text/xml (an allowed extension), the svg-sanitize branch is skipped, the <script> is stored raw, and the inline-serve path returns it as text/xml; charset=utf-8 with Content-Disposition: inline — which the browser renders as a live XHTML document and executes. The dedicated StorageHelper::allowSafeInline() whitelist that should have constrained inline-renderable types is never wired into the serve path. ### Details Vulnerable code — sanitizer keyed on finfo MIME `app/Http/Requests/UploadFileRequest.php:46-53` ```php $extension = $file->getClientOriginalExtension(); $file_name = $name_prefix.'-'.str_random(8).'-'.str_slug(...).'.'.$file->guessExtension(); ... if ($file->getMimeType() === 'image/svg+xml') { $uploaded_file = $this->handleSVG($file); // svg-sanitize fires } else { $uploaded_file = file_get_contents($file); // stored RAW — no sanitization } ``` Vulnerable code — inline serve, no `allowSafeInline()` `app/Http/Controllers/UploadedFilesController.php:103` ```php if (request('inline') == 'true') { $headers = ['Content-Disposition' => 'inline']; return Storage::download($path.$log->filename, $log->filename, $headers); } ``` `StorageHelper::allowSafeInline()` (`app/Helpers/StorageHelper.php:88`) exists to whitelist inline-renderable types but is not called here. The validation rule (`UploadFileRequest::rules()`) is `mimes`: over `config('filesystems.allowed_upload_extensions_for_validator')`, which includes svg, xml, and txt — so a text/xml file passes validation and bypasses the SVG sanitizer simultaneously. POC 1. From a fresh install, as a user with only `assets.view` + `assets.files` targeting any existing asset created by admin 2. click on the asset created by admin and upload files. 3. create a XML file with the following payload and upload it. ```xml <?xml version="1.0"?> <html xmlns="http://www.w3.org/1999/xhtml"> <head><script>alert(document.cookie)</script></head> <body>hi</body> </html> ``` 4. Noticed that it did not receive any error and the file was uploaded. 5. Now, can just get the URL and view it. (need to add the `inline=true`). image.png Notice that the XSS was able to request `document.cookie`. This means that it is possible for low privilege user to perform XSS and perform privilege escalation to admin.

CVE-2026-55466 Affected Snipe/snipe it Versions

1 component(s)
Fixed Versions:
8.6.2
Product / Package Ecosystem Affected Versions Fixed Version
snipe/snipe-it
 Packagist
< 8.6.2
8.6.2

References

GitHub Advisory / Wiki ADVISORY
https://github.com/grokability/snipe-it/security/advisories/GHSA-jhph-5q74-pmfx
NVD — CVE-2026-55466 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-55466
Security Fix Commit FIX COMMIT
https://github.com/grokability/snipe-it/commit/000cea0a622d586366cf60d2240c7c2a4b17c955
Snipe/snipe it Source Repository REPOSITORY
https://github.com/grokability/snipe-it
Snipe/snipe it Release RELEASE
https://github.com/grokability/snipe-it/releases/tag/v8.6.2

Frequently Asked Questions

What is CVE-2026-55466?
CVE-2026-55466 is a security vulnerability in Snipe/snipe it involving Snipe-IT vulnerable to stored XSS via inline-served attachment under CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting').
Which Snipe/snipe it versions are affected?
Affected versions include releases prior to 8.6.2 across affected packages: snipe/snipe-it.
What version fixes CVE-2026-55466?
Upgrading to 8.6.2 (or the latest patched release for your respective branch) resolves the vulnerability.
Is snipe/snipe-it affected?
Yes, snipe/snipe-it is affected in releases prior to 8.6.2. Upgrade your dependency to 8.6.2 or later.
What is the CVSS score of CVE-2026-55466?
CVE-2026-55466 has a CVSS v3.1 base score of 8.7 (MODERATE) with vector string CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N.
What CWE is associated with CVE-2026-55466?
CVE-2026-55466 is classified under CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') (The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.).
How can I check Packagist dependencies for CVE-2026-55466?
Run the dependency tree command: 'inspect dependencies for snipe/snipe-it'. 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-jhph-5q74-pmfx",
  "modified" : "2026-08-28T17:59:54Z",
  "published" : "2026-08-28T17:59:54Z",
  "aliases" : [ "CVE-2026-55466" ],
  "summary" : "Snipe-IT vulnerable to stored XSS via inline-served attachment",
  "details" : "### Impact\nA low-privilege user can store an active-content payload as an asset attachment and have it served inline, same-origin, with an active Content-Type, achieving stored XSS. The application sanitizes uploads only when PHP finfo detects image/svg+xml. By submitting an XHTML document whose finfo MIME is text/xml (an allowed extension), the svg-sanitize branch is skipped, the <script> is stored raw, and the inline-serve path returns it as text/xml; charset=utf-8 with Content-Disposition: inline — which the browser renders as a live XHTML document and executes. The dedicated StorageHelper::allowSafeInline() whitelist that should have constrained inline-renderable types is never wired into the serve path.\n\n### Details\nVulnerable code — sanitizer keyed on finfo MIME `app/Http/Requests/UploadFileRequest.php:46-53`\n\n```php\n$extension = $file->getClientOriginalExtension();\n$file_name = $name_prefix.'-'.str_random(8).'-'.str_slug(...).'.'.$file->guessExtension();\n...\nif ($file->getMimeType() === 'image/svg+xml') {\n    $uploaded_file = $this->handleSVG($file);   // svg-sanitize fires\n} else {\n    $uploaded_file = file_get_contents($file);   // stored RAW — no sanitization\n}\n```\n\nVulnerable code — inline serve, no `allowSafeInline()` `app/Http/Controllers/UploadedFilesController.php:103`\n\n```php\nif (request('inline') == 'true') {\n    $headers = ['Content-Disposition' => 'inline'];\n    return Storage::download($path.$log->filename, $log->filename, $headers);\n}\n```\n\n`StorageHelper::allowSafeInline()` (`app/Helpers/StorageHelper.php:88`) exists to whitelist inline-renderable types but is not called here. The validation rule (`UploadFileRequest::rules()`) is `mimes`: over `config('filesystems.allowed_upload_extensions_for_validator')`, which includes svg, xml, and txt — so a text/xml file passes validation and bypasses the SVG sanitizer simultaneously.\n\nPOC\n1. From a fresh install, as a user with only `assets.view` + `assets.files` targeting any existing asset created by admin\n2. click on the asset created by admin and upload files.\n3. create a XML file with the following payload and upload it.\n\n```xml\n<?xml version=\"1.0\"?>\n<html xmlns=\"http://www.w3.org/1999/xhtml\">\n<head><script>alert(document.cookie)</script></head>\n<body>hi</body>\n</html>\n```\n\n\n4. Noticed that it did not receive any error and the file was uploaded.\n5. Now, can just get the URL and view it. (need to add the `inline=true`).\nimage.png\n\nNotice that the XSS was able to request `document.cookie`. This means that it is possible for low privilege user to perform XSS and perform privilege escalation to admin.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N"
  }, {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:A/VC:N/VI:N/VA:N/SC:H/SI:H/SA:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Packagist",
      "name" : "snipe/snipe-it"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "8.6.2"
      } ]
    } ],
    "database_specific" : {
      "last_known_affected_version_range" : "<= 8.6.1"
    }
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/grokability/snipe-it/security/advisories/GHSA-jhph-5q74-pmfx"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-55466"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/grokability/snipe-it/commit/000cea0a622d586366cf60d2240c7c2a4b17c955"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/grokability/snipe-it"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/grokability/snipe-it/releases/tag/v8.6.2"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-79" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-08-28T17:59:54Z",
    "nvd_published_at" : "2026-07-10T20:16:46Z"
  }
}