CVE-2026-46683: Snappy SSRF And Local File Read Vulnerability

MODERATE
Advisory Identifier: GHSA-c5fp-p67m-gq56
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CWE-918
Published
Advisory Summary

CVE-2026-46683 is a MODERATE ssrf and local file read vulnerability (CWE-918: Server-Side Request Forgery (SSRF)) affecting Snappy libraries in the Packagist ecosystem. The issue involves ssrf and local file read via the xsl-style-sheet option. Remediation is available by upgrading affected packages to version 1.7.0.

CVE-2026-46683 at a Glance

CVE Identifier CVE-2026-46683
GHSA Identifier GHSA-c5fp-p67m-gq56
Severity MODERATE
CVSS v3.1 Base Score N/A
CWE Classification CWE-918: Server-Side Request Forgery (SSRF)
Affected Product Snappy
Package Ecosystem Packagist
Published Date
Last Updated

How to Fix CVE-2026-46683

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

knplabs/knp-snappy fixed: 1.7.0 
Upgrade knplabs/knp-snappy to 1.7.0
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 knplabs/knp-snappy

How to Check if You Are Affected

To determine whether your application is affected by CVE-2026-46683, inspect your project dependencies for Snappy:

inspect dependencies for knplabs/knp-snappy

Analyze the terminal output to locate any version of Snappy in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 1.7.0), 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 Snappy, 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 It impacts applications where: - the PHP daemon run with root permissions ; - the application is either running outside a container or has sensitive file access ; It could happens with this kind of workflows: ```php $stylesheet = $_GET['stylesheet']; // = ‘file:///etc/passwd’ $pdf = new Knp\Snappy\Pdf(‘/usr/local/bin/wkhtmltopdf’); $pdf->generate(‘page.html’, ‘out.pdf’, [ ‘xsl-style-sheet’ => $stylesheet ]); ``` ### Patches A list a schema with `http` and `https` by default is used to validate the remote path by default. ### Workarounds Developers should ensure usage cannot allow (in any case) a user to pass a free input directly to the Snappy library. ```php // Bad example $pdf = new Knp\Snappy\Pdf(‘/usr/local/bin/wkhtmltopdf’); $pdf->generate(‘page.html’, ‘out.pdf’, [ ‘xsl-style-sheet’ => $_GET['input'], ]); ``` Instead developers can list available available stylesheets and pick the right one with the user input. ```php // Better $allowedStylesheets = [ 'invoice' => '/app/xsl/invoice.xsl', 'report' => '/app/xsl/report.xsl', ]; $key = $_GET['stylesheet'] ?? ''; if (!array_key_exists($key, $allowedStylesheets)) { throw new \RuntimeException('Unknown stylesheet.'); } $pdf = new Knp\Snappy\Pdf('/usr/local/bin/wkhtmltopdf'); $pdf->generate('page.html', 'out.pdf', [ 'xsl-style-sheet' => $allowedStylesheets[$key], ]); ``` ### References Read more about SSRF at [owasp.org/www-community/attacks/Server_Side_Request_Forgery](https://owasp.org/www-community/attacks/Server_Side_Request_Forgery)

CVE-2026-46683 Affected Snappy Versions

1 component(s)
Fixed Versions:
1.7.0
Product / Package Ecosystem Affected Versions Fixed Version
knplabs/knp-snappy
 Packagist
< 1.7.0
1.7.0

References

GitHub Advisory / Wiki ADVISORY
https://github.com/KnpLabs/snappy/security/advisories/GHSA-c5fp-p67m-gq56
NVD — CVE-2026-46683 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-46683
Snappy Source Repository REPOSITORY
https://github.com/KnpLabs/snappy
Snappy Release RELEASE
https://github.com/KnpLabs/snappy/releases/tag/v1.7.0

Frequently Asked Questions

What is CVE-2026-46683?
CVE-2026-46683 is a security vulnerability in Snappy involving SSRF and local file read via the xsl-style-sheet option under CWE-918: Server-Side Request Forgery (SSRF).
Which Snappy versions are affected?
Affected versions include releases prior to 1.7.0 across affected packages: knplabs/knp-snappy.
What version fixes CVE-2026-46683?
Upgrading to 1.7.0 (or the latest patched release for your respective branch) resolves the vulnerability.
Is knplabs/knp-snappy affected?
Yes, knplabs/knp-snappy is affected in releases prior to 1.7.0. Upgrade your dependency to 1.7.0 or later.
What CWE is associated with CVE-2026-46683?
CVE-2026-46683 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 Packagist dependencies for CVE-2026-46683?
Run the dependency tree command: 'inspect dependencies for knplabs/knp-snappy'. 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-c5fp-p67m-gq56",
  "modified" : "2026-06-11T13:30:20Z",
  "published" : "2026-05-21T20:20:01Z",
  "aliases" : [ "CVE-2026-46683" ],
  "summary" : "Snappy : SSRF and local file read via the xsl-style-sheet option",
  "details" : "### Impact\n\nIt impacts applications where:\n- the PHP daemon run with root permissions ;\n- the application is either running outside a container or has sensitive file access ;\n\nIt could happens with this kind of workflows:\n\n```php\n$stylesheet = $_GET['stylesheet']; // = ‘file:///etc/passwd’\n$pdf = new Knp\\Snappy\\Pdf(‘/usr/local/bin/wkhtmltopdf’);\n $pdf->generate(‘page.html’, ‘out.pdf’, [\n   ‘xsl-style-sheet’ => $stylesheet\n ]);\n```\n\n### Patches\n\nA list a schema with `http` and `https` by default is used to validate the remote path by default.\n\n### Workarounds\n\nDevelopers should ensure usage cannot allow (in any case) a user to pass a free input directly to the Snappy library.\n\n```php\n// Bad example\n$pdf = new Knp\\Snappy\\Pdf(‘/usr/local/bin/wkhtmltopdf’);\n $pdf->generate(‘page.html’, ‘out.pdf’, [\n   ‘xsl-style-sheet’ => $_GET['input'],\n ]);\n```\n\nInstead developers can list available available stylesheets and pick the right one with the user input.\n\n```php\n// Better\n$allowedStylesheets = [\n    'invoice' => '/app/xsl/invoice.xsl',\n    'report'  => '/app/xsl/report.xsl',\n];\n\n$key = $_GET['stylesheet'] ?? '';\n\nif (!array_key_exists($key, $allowedStylesheets)) {\n    throw new \\RuntimeException('Unknown stylesheet.');\n}\n\n$pdf = new Knp\\Snappy\\Pdf('/usr/local/bin/wkhtmltopdf');\n$pdf->generate('page.html', 'out.pdf', [\n    'xsl-style-sheet' => $allowedStylesheets[$key],\n]);\n```\n\n### References\n\nRead more about SSRF at [owasp.org/www-community/attacks/Server_Side_Request_Forgery](https://owasp.org/www-community/attacks/Server_Side_Request_Forgery)",
  "severity" : [ {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:L/SI:L/SA:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Packagist",
      "name" : "knplabs/knp-snappy"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "1.7.0"
      } ]
    } ],
    "database_specific" : {
      "last_known_affected_version_range" : "<= 1.6.0"
    }
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/KnpLabs/snappy/security/advisories/GHSA-c5fp-p67m-gq56"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-46683"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/KnpLabs/snappy"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/KnpLabs/snappy/releases/tag/v1.7.0"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-918" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-05-21T20:20:01Z",
    "nvd_published_at" : "2026-06-10T20:17:29Z"
  }
}