CVE-2026-101274
Full vulnerability record from the local CVENow database.
Description
When pretix is used as the identity provider in a Single-Sign-On (SSO) setup for customer accounts, the system did not properly validate the `response_type` requested in an authorization request against the configured grant type of the SSO client. This means that if an SSO client was configured to only allow the `code` response type, which requires knowledge of the client secret to use and would wrongfully send a response type like `id_token`, it would receive back a valid token. Exploiting this requires the attacker to run JavaScript on the page specified by `redirect_uri`, which must be from a list specified in the client configuration.
Severity
MEDIUM
CVSS score
6.9
(v4.0)
Vulnerability status
Deferred
Source identifier
655498c3-6ec5-4f0b-aea6-853b334d05a6
Published
2026-10-28 11:17:13.577000
Last modified
2026-10-28 15:24:56.033000
View original CVE JSON
{
"id": "CVE-2026-101274",
"sourceIdentifier": "655498c3-6ec5-4f0b-aea6-853b334d05a6",
"published": "2026-10-28T11:17:13.577",
"lastModified": "2026-10-28T15:24:56.033",
"vulnStatus": "Deferred",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "When pretix is used as the identity provider in a Single-Sign-On (SSO) setup for customer accounts, the system did not properly validate the `response_type` requested in an authorization request against the configured grant type of the SSO client. This means that if an SSO client was configured to only allow the `code` response type, which requires knowledge of the client secret to use and would wrongfully send a response type like `id_token`, it would receive back a valid token. Exploiting this requires the attacker to run JavaScript on the page specified by `redirect_uri`, which must be from a list specified in the client configuration."
}
],
"affected": [
{
"source": "655498c3-6ec5-4f0b-aea6-853b334d05a6",
"affectedData": [
{
"vendor": "pretix",
"defaultStatus": "unaffected",
"collectionURL": "https://pypi.python.org",
"packageName": "pretix",
"repo": "https://github.com/pretix/pretix",
"versions": [
{
"version": "0",
"lessThan": "2026.6.4",
"versionType": "python",
"status": "affected"
},
{
"version": "2026.7.0",
"lessThan": "2026.7.3",
"versionType": "python",
"status": "affected"
},
{
"version": "2026.8.0",
"lessThan": "2026.8.1",
"versionType": "python",
"status": "affected"
}
]
}
]
}
],
"metrics": {
"cvssMetricV40": [
{
"source": "655498c3-6ec5-4f0b-aea6-853b334d05a6",
"type": "Secondary",
"cvssData": {
"version": "4.0",
"vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:P/VC:H/VI:L/VA:N/SC:H/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",
"baseScore": 6.9,
"baseSeverity": "MEDIUM",
"attackVector": "NETWORK",
"attackComplexity": "LOW",
"attackRequirements": "PRESENT",
"privilegesRequired": "HIGH",
"userInteraction": "PASSIVE",
"vulnConfidentialityImpact": "HIGH",
"vulnIntegrityImpact": "LOW",
"vulnAvailabilityImpact": "NONE",
"subConfidentialityImpact": "HIGH",
"subIntegrityImpact": "NONE",
"subAvailabilityImpact": "NONE",
"exploitMaturity": "NOT_DEFINED",
"confidentialityRequirement": "NOT_DEFINED",
"integrityRequirement": "NOT_DEFINED",
"availabilityRequirement": "NOT_DEFINED",
"modifiedAttackVector": "NOT_DEFINED",
"modifiedAttackComplexity": "NOT_DEFINED",
"modifiedAttackRequirements": "NOT_DEFINED",
"modifiedPrivilegesRequired": "NOT_DEFINED",
"modifiedUserInteraction": "NOT_DEFINED",
"modifiedVulnConfidentialityImpact": "NOT_DEFINED",
"modifiedVulnIntegrityImpact": "NOT_DEFINED",
"modifiedVulnAvailabilityImpact": "NOT_DEFINED",
"modifiedSubConfidentialityImpact": "NOT_DEFINED",
"modifiedSubIntegrityImpact": "NOT_DEFINED",
"modifiedSubAvailabilityImpact": "NOT_DEFINED",
"Safety": "NOT_DEFINED",
"Automatable": "NOT_DEFINED",
"Recovery": "NOT_DEFINED",
"valueDensity": "NOT_DEFINED",
"vulnerabilityResponseEffort": "NOT_DEFINED",
"providerUrgency": "NOT_DEFINED"
}
}
]
},
"references": [
{
"url": "https://pretix.eu/about/en/blog/20261028-release-2026-8-1/",
"source": "655498c3-6ec5-4f0b-aea6-853b334d05a6"
}
]
}