CVE-2026-42552: Flightphp/core Flight Vulnerable To Sensitive Information Vulnerability
HIGHCVE-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
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).
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.
Upgrade flightphp/core to 3.18.1
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
CVE-2026-42552 Affected Flightphp/core Versions
1 component(s)| 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?
Which Flightphp/core versions are affected?
What version fixes CVE-2026-42552?
Is flightphp/core affected?
What is the CVSS score of CVE-2026-42552?
What CWE is associated with CVE-2026-42552?
How can I check Packagist dependencies for CVE-2026-42552?
Machine-readable OSV JSON
OSV v1.5 Schema
{
"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"
}
}