CVE-2026-42552: Flightphp/core Flight Vulnerable To Sensitive Information Vulnerability

HIGH
Advisory Identifier: GHSA-qrch-52m5-vv85
CVSS 7.5
CWE-209
Published
Advisory Summary

CVE-2026-42552 is a HIGH (CVSS 7.5) flight vulnerable to sensitive information vulnerability (CWE-209: Generation of Error Message Containing Sensitive Information) affecting Flightphp/core libraries in the Packagist ecosystem. The issue involves flight vulnerable to sensitive information disclosure via default error handler. Remediation is available by upgrading affected packages to version 3.18.1.

CVE-2026-42552 at a Glance

CVE Identifier CVE-2026-42552
GHSA Identifier GHSA-qrch-52m5-vv85
Severity HIGH
CVSS v3.1 Base Score 7.5
CWE Classification CWE-209: Generation of Error Message Containing Sensitive Information
Affected Product Flightphp/core
Package Ecosystem Packagist
Published Date
Last Updated

Security Impact

CVSS: 7.5

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:U/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 Unchanged (S:U)
Confidentiality High (C:H)
Integrity None (I:N)
Availability None (A:N)

How to Fix CVE-2026-42552

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

flightphp/core fixed: 3.18.1
Upgrade flightphp/core to 3.18.1
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 flightphp/core

How to Check if You Are Affected

To determine whether your application is affected by CVE-2026-42552, inspect your project dependencies for Flightphp/core:

inspect dependencies for flightphp/core

Analyze the terminal output to locate any version of Flightphp/core in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 3.18.1), 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-209: Generation of Error Message Containing Sensitive Information, where the product generates an error message that includes sensitive information about its environment, users, or associated data. In Flightphp/core, 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 The default error handler `Engine::_error()` writes the full exception message, exception code, and stack trace (including absolute filesystem paths) directly into the HTTP 500 response, with no debug gating. Production deployments leak internal paths, any secret interpolated into an exception message, and full module structure — giving attackers primitives for chaining other weaknesses (LFI, path traversal). ### Affected code `flight/Engine.php` (≈ lines 678-704): ```php public function _error(Throwable $e): void { ... $msg = sprintf(<<<'HTML' <h1>500 Internal Server Error</h1> <h3>%s (%s)</h3> <pre>%s</pre> HTML, $e->getMessage(), $e->getCode(), $e->getTraceAsString() ); $this->response()->cache(0)->clearBody()->status(500)->write($msg)->send(); } ``` No `flight.debug` check, no environment gating. ### Proof of concept Any uncaught exception — including those auto-raised from `handleError()` — returns: ``` HTTP/1.1 500 Internal Server Error <h1>500 Internal Server Error</h1> <h3>secret path /var/www/config/db.yml; token=LEAKED123 (0)</h3> <pre>#0 [internal function]: {closure}() #1 /home/user/app/vendor/flightphp/core/flight/core/Dispatcher.php(361)... #2 /home/user/app/vendor/flightphp/core/flight/Engine.php(...) ... </pre> ``` Reproduced against the live PoC app at `/poc5/error`. ### Impact - Disclosure of absolute filesystem paths (primes weaponization of LFI / path-traversal vulnerabilities in the same application). - Disclosure of secrets (DB credentials, API tokens) when exceptions are constructed with interpolated configuration values. - Enumeration of installed vendor packages and internal application structure. ### Patch (fixed in `3.18.1`, commit `b8dd23a`) A new `flight.debug` setting (default `false`) gates the verbose output. In production the handler now emits only `<h1>500 Internal Server Error</h1>`. Developers can set `flight.debug = true` in local environments to restore the full trace output. ### Credit Discovered by **@Rootingg**.

CVE-2026-42552 Affected Flightphp/core Versions

1 component(s)
Fixed Versions:
3.18.1
Product / Package Ecosystem Affected Versions Fixed Version
flightphp/core
Packagist
< 3.18.1
3.18.1

References

Frequently Asked Questions

What is CVE-2026-42552?
CVE-2026-42552 is a security vulnerability in Flightphp/core involving Flight vulnerable to sensitive information disclosure via default error handler under CWE-209: Generation of Error Message Containing Sensitive Information.
Which Flightphp/core versions are affected?
Affected versions include releases prior to 3.18.1 across affected packages: flightphp/core.
What version fixes CVE-2026-42552?
Upgrading to 3.18.1 (or the latest patched release for your respective branch) resolves the vulnerability.
Is flightphp/core affected?
Yes, flightphp/core is affected in releases prior to 3.18.1. Upgrade your dependency to 3.18.1 or later.
What is the CVSS score of CVE-2026-42552?
CVE-2026-42552 has a CVSS v3.1 base score of 7.5 (HIGH) with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N.
What CWE is associated with CVE-2026-42552?
CVE-2026-42552 is classified under CWE-209: Generation of Error Message Containing Sensitive Information (The product generates an error message that includes sensitive information about its environment, users, or associated data.).
How can I check Packagist dependencies for CVE-2026-42552?
Run the dependency tree command: 'inspect dependencies for flightphp/core'. 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-qrch-52m5-vv85",
  "modified" : "2026-05-14T20:42:12Z",
  "published" : "2026-05-06T21:39:07Z",
  "aliases" : [ "CVE-2026-42552" ],
  "summary" : "Flight vulnerable to sensitive information disclosure via default error handler",
  "details" : "### Summary\nThe default error handler `Engine::_error()` writes the full exception message, exception code, and stack trace (including absolute filesystem paths) directly into the HTTP 500 response, with no debug gating. Production deployments leak internal paths, any secret interpolated into an exception message, and full module structure — giving attackers primitives for chaining other weaknesses (LFI, path traversal).\n\n### Affected code\n`flight/Engine.php` (≈ lines 678-704):\n\n```php\npublic function _error(Throwable $e): void\n{\n    ...\n    $msg = sprintf(<<<'HTML'\n        <h1>500 Internal Server Error</h1>\n            <h3>%s (%s)</h3>\n            <pre>%s</pre>\n        HTML,\n        $e->getMessage(),\n        $e->getCode(),\n        $e->getTraceAsString()\n    );\n    $this->response()->cache(0)->clearBody()->status(500)->write($msg)->send();\n}\n```\n\nNo `flight.debug` check, no environment gating.\n\n### Proof of concept\nAny uncaught exception — including those auto-raised from `handleError()` — returns:\n\n```\nHTTP/1.1 500 Internal Server Error\n\n<h1>500 Internal Server Error</h1>\n  <h3>secret path /var/www/config/db.yml; token=LEAKED123 (0)</h3>\n  <pre>#0 [internal function]: {closure}()\n  #1 /home/user/app/vendor/flightphp/core/flight/core/Dispatcher.php(361)...\n  #2 /home/user/app/vendor/flightphp/core/flight/Engine.php(...)\n  ...\n  </pre>\n```\n\nReproduced against the live PoC app at `/poc5/error`.\n\n### Impact\n- Disclosure of absolute filesystem paths (primes weaponization of LFI / path-traversal vulnerabilities in the same application).\n- Disclosure of secrets (DB credentials, API tokens) when exceptions are constructed with interpolated configuration values.\n- Enumeration of installed vendor packages and internal application structure.\n\n### Patch (fixed in `3.18.1`, commit `b8dd23a`)\nA new `flight.debug` setting (default `false`) gates the verbose output. In production the handler now emits only `<h1>500 Internal Server Error</h1>`. Developers can set `flight.debug = true` in local environments to restore the full trace output.\n\n### Credit\nDiscovered by **@Rootingg**.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Packagist",
      "name" : "flightphp/core"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "3.18.1"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/flightphp/core/security/advisories/GHSA-qrch-52m5-vv85"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-42552"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/flightphp/core/commit/b8dd23aaa828cb289fa3c84e75b2a3717cab50b0"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/flightphp/core"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/flightphp/core/releases/tag/v3.18.1"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-209" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-05-06T21:39:07Z",
    "nvd_published_at" : "2026-05-13T20:16:22Z"
  }
}