CVE-2019-18886: Symfony/security http User Enumeration Leak Using Switch Vulnerability
MODERATECVE-2019-18886 is a MODERATE (CVSS 5.3) user enumeration leak using switch vulnerability (CWE-203: Observable Discrepancy) affecting Symfony/security http libraries in the Packagist ecosystem. The issue involves user enumeration leak using switch user functionality in symfony. Remediation is available by upgrading affected packages to version 4.2.12, 4.3.8.
CVE-2019-18886 at a Glance
Security Impact
CVSS: 5.3
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:L/I:N/A:N).
How to Fix CVE-2019-18886
To remediate this vulnerability, upgrade all affected Symfony/security http 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 symfony/security-http to 4.2.12Upgrade symfony/security-http to 4.3.8Upgrade symfony/symfony to 4.2.12Upgrade symfony/symfony to 4.3.8Run the following command in your project directory to verify that all resolved dependencies use the patched release:
inspect dependencies for symfony/security-httpHow to Check if You Are Affected
To determine whether your application is affected by CVE-2019-18886, inspect your project dependencies for Symfony/security http:
inspect dependencies for symfony/security-httpAnalyze the terminal output to locate any version of Symfony/security http in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 4.2.12), 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-203: Observable Discrepancy, where the product behaves differently or sends different responses under different circumstances in a way that is observable to an unauthorized actor. In Symfony/security http, 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-2019-18886 Affected Symfony/security http Versions
4 component(s)| Product / Package | Ecosystem | Affected Versions | Fixed Version |
|---|---|---|---|
|
symfony/security-http
|
Packagist |
≥ 4.1.0
< 4.2.12
|
4.2.12
|
|
symfony/security-http
|
Packagist |
≥ 4.3.0
< 4.3.8
|
4.3.8
|
|
symfony/symfony
|
Packagist |
≥ 4.1.0
< 4.2.12
|
4.2.12
|
|
symfony/symfony
|
Packagist |
≥ 4.3.0
< 4.3.8
|
4.3.8
|
References
Frequently Asked Questions
What is CVE-2019-18886?
Which Symfony/security http versions are affected?
What version fixes CVE-2019-18886?
Is symfony/security-http affected?
Is symfony/symfony affected?
What is the CVSS score of CVE-2019-18886?
What CWE is associated with CVE-2019-18886?
How can I check Packagist dependencies for CVE-2019-18886?
Machine-readable OSV JSON
OSV v1.5 Schema
{
"schema_version" : "1.4.0",
"id" : "GHSA-4vpc-5jx4-cfqg",
"modified" : "2021-07-28T15:49:16Z",
"published" : "2019-12-02T18:09:21Z",
"aliases" : [ "CVE-2019-18886" ],
"summary" : "User enumeration leak using switch user functionality in Symfony",
"details" : "An issue was discovered in Symfony 4.2.0 to 4.2.11 and 4.3.0 to 4.3.7. The ability to enumerate users was possible due to different handling depending on whether the user existed when making unauthorized attempts to use the switch users functionality. This is related to symfony/security.",
"severity" : [ {
"type" : "CVSS_V3",
"score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N"
} ],
"affected" : [ {
"package" : {
"ecosystem" : "Packagist",
"name" : "symfony/security-http"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "4.1.0"
}, {
"fixed" : "4.2.12"
} ]
} ]
}, {
"package" : {
"ecosystem" : "Packagist",
"name" : "symfony/security-http"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "4.3.0"
}, {
"fixed" : "4.3.8"
} ]
} ]
}, {
"package" : {
"ecosystem" : "Packagist",
"name" : "symfony/symfony"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "4.1.0"
}, {
"fixed" : "4.2.12"
} ]
} ]
}, {
"package" : {
"ecosystem" : "Packagist",
"name" : "symfony/symfony"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "4.3.0"
}, {
"fixed" : "4.3.8"
} ]
} ]
} ],
"references" : [ {
"type" : "ADVISORY",
"url" : "https://nvd.nist.gov/vuln/detail/CVE-2019-18886"
}, {
"type" : "WEB",
"url" : "https://github.com/FriendsOfPHP/security-advisories/blob/master/symfony/security-http/CVE-2019-18886.yaml"
}, {
"type" : "WEB",
"url" : "https://github.com/FriendsOfPHP/security-advisories/blob/master/symfony/symfony/CVE-2019-18886.yaml"
}, {
"type" : "WEB",
"url" : "https://github.com/symfony/symfony/releases/tag/v4.3.8"
}, {
"type" : "WEB",
"url" : "https://symfony.com/blog/cve-2019-18886-prevent-user-enumeration-using-switch-user-functionality"
}, {
"type" : "WEB",
"url" : "https://symfony.com/blog/symfony-4-3-8-released"
}, {
"type" : "WEB",
"url" : "https://symfony.com/cve-2019-18886"
} ],
"database_specific" : {
"cwe_ids" : [ "CWE-200", "CWE-203" ],
"severity" : "MODERATE",
"github_reviewed" : true,
"github_reviewed_at" : "2019-12-01T19:47:26Z",
"nvd_published_at" : "2019-11-21T18:15:00Z"
}
}