FKIE_CVE-2026-121971
Vulnerability from fkie_nvd - Published: 2026-11-04 18:17 - Updated: 2026-11-05 19:17
Severity
Summary
The component ScopingHttpClient in Symfony HttpClient merges the options of its default scope (such as auth_bearer or auth_basic) into a request before resolving a relative URL against the base_uri, allowing a network-path reference such as "//evil.example/steal" to be sent to another origin together with the default scope’s credentials, and resulting in potential disclosure of those credentials to an attacker-controlled server. This affects Symfony in versions 5.x prior to 5.4.56, 6.x prior to 6.4.50, 7.x prior to 7.4.23, and 8.x prior to 8.1.11.
The resolved URL falls outside the origin of the base URI, yet it keeps the merged options, whereas the absolute spelling "https://evil.example/steal" receives none. The same happens with a different port or user-info part on the same host.
This is reachable whenever an attacker controls the beginning of a URL passed to a client built with a base_uri and credentials, including those created with HttpClient::createForBaseUri() or configured under framework.http_client.scoped_clients.
To solve the issue, after resolving a relative URL against the base URI of the default scope, ScopingHttpClient now compares the scheme and authority of the result with those of the base URI, parsed the way the request is sent.
References
Impacted products
| Vendor | Product | Version |
|---|
{
"affected": [
{
"affectedData": [
{
"collectionURL": "https://packagist.org/packages/symfony/http-client",
"defaultStatus": "unaffected",
"modules": [
"Symfony\\Component\\HttpClient\\ScopingHttpClient"
],
"packageName": "symfony/http-client",
"product": "symfony",
"repo": "https://github.com/symfony/http-client",
"vendor": "sensiolabs",
"versions": [
{
"lessThan": "5.4.56",
"status": "affected",
"version": "0",
"versionType": "git"
},
{
"lessThan": "6.4.50",
"status": "affected",
"version": "6.0.0",
"versionType": "git"
},
{
"lessThan": "7.4.23",
"status": "affected",
"version": "7.0.0",
"versionType": "git"
},
{
"lessThan": "8.1.11",
"status": "affected",
"version": "8.0.0",
"versionType": "git"
}
]
}
],
"source": "596c5446-0ce5-4ba2-aa66-48b3b757a647"
}
],
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "The component ScopingHttpClient\u00a0in Symfony HttpClient\u00a0merges the options of its default scope (such as auth_bearer or auth_basic) into a request before resolving a relative URL against the base_uri, allowing a network-path reference such as \"//evil.example/steal\"\u00a0to be sent to another origin together with the default scope\u2019s credentials, and resulting in potential disclosure of those credentials to an attacker-controlled server.\u00a0This affects Symfony in versions 5.x prior to 5.4.56, 6.x prior to 6.4.50, 7.x prior to 7.4.23, and 8.x prior to 8.1.11.\n\n\n\nThe resolved URL falls outside the origin of the base URI, yet it keeps the merged options, whereas the absolute spelling \"https://evil.example/steal\" receives none. The same happens with a different port or user-info part on the same host.\n\n\n\n\n\n\n\n\n\nThis is reachable whenever an attacker controls the beginning of a URL passed to a client built with a base_uri\u00a0and credentials, including those created with HttpClient::createForBaseUri()\u00a0or configured under framework.http_client.scoped_clients.\n\nTo solve the issue, after\u00a0resolving a relative URL against the base URI of the default scope, ScopingHttpClient now compares the scheme and authority of the result with those of the base URI, parsed the way the request is sent."
}
],
"id": "CVE-2026-121971",
"lastModified": "2026-11-05T19:17:16.063",
"metrics": {
"cvssMetricV40": [
{
"cvssData": {
"Automatable": "NOT_DEFINED",
"Recovery": "NOT_DEFINED",
"Safety": "NOT_DEFINED",
"attackComplexity": "LOW",
"attackRequirements": "PRESENT",
"attackVector": "NETWORK",
"availabilityRequirement": "NOT_DEFINED",
"baseScore": 8.2,
"baseSeverity": "HIGH",
"confidentialityRequirement": "NOT_DEFINED",
"exploitMaturity": "NOT_DEFINED",
"integrityRequirement": "NOT_DEFINED",
"modifiedAttackComplexity": "NOT_DEFINED",
"modifiedAttackRequirements": "NOT_DEFINED",
"modifiedAttackVector": "NOT_DEFINED",
"modifiedPrivilegesRequired": "NOT_DEFINED",
"modifiedSubAvailabilityImpact": "NOT_DEFINED",
"modifiedSubConfidentialityImpact": "NOT_DEFINED",
"modifiedSubIntegrityImpact": "NOT_DEFINED",
"modifiedUserInteraction": "NOT_DEFINED",
"modifiedVulnAvailabilityImpact": "NOT_DEFINED",
"modifiedVulnConfidentialityImpact": "NOT_DEFINED",
"modifiedVulnIntegrityImpact": "NOT_DEFINED",
"privilegesRequired": "NONE",
"providerUrgency": "NOT_DEFINED",
"subAvailabilityImpact": "NONE",
"subConfidentialityImpact": "NONE",
"subIntegrityImpact": "NONE",
"userInteraction": "NONE",
"valueDensity": "NOT_DEFINED",
"vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
"version": "4.0",
"vulnAvailabilityImpact": "NONE",
"vulnConfidentialityImpact": "HIGH",
"vulnIntegrityImpact": "NONE",
"vulnerabilityResponseEffort": "NOT_DEFINED"
},
"source": "596c5446-0ce5-4ba2-aa66-48b3b757a647",
"type": "Secondary"
}
],
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"id": "CVE-2026-121971",
"options": [
{
"exploitation": "none"
},
{
"automatable": "no"
},
{
"technicalImpact": "partial"
}
],
"role": "CISA Coordinator",
"timestamp": "2026-11-04T21:11:51.149301Z",
"version": "2.0.3"
}
}
]
},
"published": "2026-11-04T18:17:43.077",
"references": [
{
"source": "596c5446-0ce5-4ba2-aa66-48b3b757a647",
"url": "https://github.com/symfony/symfony/commit/64c34e85bd03b3f8a735d8e1af393659dda91d7c"
},
{
"source": "596c5446-0ce5-4ba2-aa66-48b3b757a647",
"url": "https://github.com/symfony/symfony/security/advisories/GHSA-gq53-v8w2-gjhj"
}
],
"sourceIdentifier": "596c5446-0ce5-4ba2-aa66-48b3b757a647",
"vulnStatus": "Received",
"weaknesses": [
{
"description": [
{
"lang": "en",
"value": "CWE-200"
},
{
"lang": "en",
"value": "CWE-522"
}
],
"source": "596c5446-0ce5-4ba2-aa66-48b3b757a647",
"type": "Secondary"
}
]
}
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