Medium
Security advisory
This affects the package clearance before 2.5.0. The vulnerability can be possible when users are able to set the value of session[:return_to]. If the value used for return_to contains multiple leading slashes (/////example.com) the user ends up being redirected to the external domain that comes after the slashes (http://example.com).
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2021-23435
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 11:40 UTC · Revision 1
Source evidence
This affects the package clearance before 2.5.0. The vulnerability can be possible when users are able to set the value of session[:return_to]. If the value used for return_to contains multiple leading slashes (/////example.com) the user ends up being redirected to the external domain that comes after the slashes (http://example.com).
osv:CVE-2021-23435
Complete source record
{
"id": "68da0610e1b533dec9de6d422dd33fe8aab3db6a429836d95c4c29bf388d5681",
"url": "https://osv.dev/vulnerability/CVE-2021-23435",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "CVE-2021-23435",
"summary": "This affects the package clearance before 2.5.0. The vulnerability can be possible when users are able to set the value of session[:return_to]. If the value used for return_to contains multiple leading slashes (/////example.com) the user ends up being redirected to the external domain that comes after the slashes (http://example.com).",
"evidence": "osv:CVE-2021-23435",
"products": [],
"severity": "medium",
"structured": {
"id": "CVE-2021-23435",
"aliases": [
"CVE-2021-23435",
"GHSA-4hpq-rjcx-7vj9",
"SNYK-RUBY-CLEARANCE-1577284"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N"
}
],
"affected": [
{
"ranges": [
{
"repo": "https://github.com/thoughtbot/clearance",
"type": "GIT",
"events": [
{
"introduced": "0"
},
{
"fixed": "3691c23b8447071ba3f6aa6f6f9e30dd3bc2ed6f"
}
],
"database_specific": {
"extracted_events": [
{
"cpe": "cpe:2.3:a:thoughtbot:clearance:*:*:*:*:*:*:*:*",
"range": [
{
"introduced": "0"
},
{
"fixed": "2.5.0"
}
],
"source": "CPE_RANGE"
}
]
}
}
],
"versions": [
"v2.4.0",
"v2.3.1",
"v2.3.0",
"v2.2.0",
"v2.1.0",
"v2.0.0",
"v1.17.0",
"v1.16.2",
"v1.16.1",
"v1.16.0",
"v1.15.1",
"v1.15.0",
"v1.14.2",
"v1.14.1",
"v1.14.0",
"v1.13.0",
"v1.12.1",
"v1.12.0",
"v1.11.0",
"v1.10.1",
"v1.10.0",
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"v1.8.1",
"v1.8.0",
"v1.7.0",
"v1.6.1",
"v1.6.0",
"v1.5.1",
"v1.5.0",
"v1.4.3",
"v1.4.2",
"v1.4.1",
"v1.4.0",
"v1.3.0",
"v1.2.1",
"v1.2.0",
"v1.1.0",
"v1.0.1",
"v1.0.0",
"v1.0.0.rc8",
"v1.0.0.rc7",
"v1.0.0.rc5",
"v1.0.0.rc4",
"v1.0.0.rc3",
"v1.0.0.rc2",
"v1.0.0.rc1",
"v0.16.2",
"v0.16.0",
"v0.15.0",
"v0.14.0",
"v0.13.1",
"v0.13.0",
"v0.12.0",
"v0.11.2",
"v0.11.1",
"v0.11.0",
"v0.10.5",
"v0.10.4",
"v0.10.3.2",
"v0.10.3.1",
"v0.10.3",
"v0.10.0",
"v0.9.1",
"v0.9.0.rc9",
"v0.9.0.rc8",
"v0.9.0.rc7",
"v0.9.0.rc6",
"v0.9.0.rc5",
"v0.9.0.rc4",
"v0.9.0.rc3",
"v0.9.0.rc2",
"v0.9.0",
"v0.8.8",
"v0.8.7",
"v0.8.6",
"v0.8.5",
"v0.8.4",
"v0.8.3",
"v0.8.2",
"v0.8.1",
"v0.8.0",
"v0.7.0",
"v0.6.9",
"v0.6.8",
"v0.6.7",
"v0.6.6",
"v0.6.5",
"v0.6.4",
"v0.6.3",
"v0.6.2",
"v0.6.1",
"v0.6.0",
"v0.5.6",
"v0.5.5",
"v0.5.4",
"v0.5.3",
"0.5.2",
"0.5.1",
"v0.5.0",
"0.4.9",
"v0.4.4",
"v0.3.7"
],
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-23435.json"
}
}
],
"modified": "2026-10-20T10:54:32.653533920Z",
"provider": "osv",
"references": [
"https://snyk.io/vuln/SNYK-RUBY-CLEARANCE-1577284",
"https://github.com/thoughtbot/clearance/pull/945"
],
"provider_metadata": {}
},
"related_cves": [
{
"value": "CVE-2021-23435",
"evidence": "/id"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 385538,
"published_at": "2021-09-12T20:15:07.443+00:00"
}