RabbitMQ: Plaintext username:password stored in an insecure cookie after successful POST /login
RabbitMQ is a messaging and streaming broker. From 4.2.0 until 4.2.8 and 4.3.2, a successful POST /login caused is_authorized/2 to set an auth cookie containing base64-encoded username:password credentials without HttpOnly, Secure, SameSite, or expiration protections. Because base64 is encoding rather than encryption, an attacker with same-origin cross-site scripting, an HTTP-readable network position, or local access to the browser cookie store could recover the actual login credentials; older browsers that treated an absent SameSite attribute as None also sent the cookie cross-site. This issue is fixed in versions 4.2.8 and 4.3.2.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2026-67236
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 8 Nov 2026, 00:53 UTC · Revision 1
Source evidence
RabbitMQ: Plaintext username:password stored in an insecure cookie after successful POST /login
core-osv · Original sourcePublished 25 Sept 2026, 15:59 UTC
RabbitMQ is a messaging and streaming broker. From 4.2.0 until 4.2.8 and 4.3.2, a successful POST /login caused is_authorized/2 to set an auth cookie containing base64-encoded username:password credentials without HttpOnly, Secure, SameSite, or expiration protections. Because base64 is encoding rather than encryption, an attacker with same-origin cross-site scripting, an HTTP-readable network position, or local access to the browser cookie store could recover the actual login credentials; older browsers that treated an absent SameSite attribute as None also sent the cookie cross-site. This issue is fixed in versions 4.2.8 and 4.3.2.
osv:CVE-2026-67236
Complete source record
{
"id": "f6ef6fe5829ef6139312ef5c191fcdfd86e6cd29789b0e544123e7bcabd12649",
"url": "https://osv.dev/vulnerability/CVE-2026-67236",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "RabbitMQ: Plaintext username:password stored in an insecure cookie after successful POST /login",
"summary": "RabbitMQ is a messaging and streaming broker. From 4.2.0 until 4.2.8 and 4.3.2, a successful POST /login caused is_authorized/2 to set an auth cookie containing base64-encoded username:password credentials without HttpOnly, Secure, SameSite, or expiration protections. Because base64 is encoding rather than encryption, an attacker with same-origin cross-site scripting, an HTTP-readable network position, or local access to the browser cookie store could recover the actual login credentials; older browsers that treated an absent SameSite attribute as None also sent the cookie cross-site. This issue is fixed in versions 4.2.8 and 4.3.2.",
"evidence": "osv:CVE-2026-67236",
"products": [],
"severity": "high",
"structured": {
"id": "CVE-2026-67236",
"aliases": [
"BIT-rabbitmq-2026-67236",
"CVE-2026-67236",
"GHSA-88vh-gx85-p36m"
],
"metrics": [
{
"type": "CVSS_V4",
"score": "CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N"
}
],
"affected": [
{
"ranges": [
{
"repo": "https://github.com/rabbitmq/rabbitmq-server",
"type": "GIT",
"events": [
{
"introduced": "95c501fbad76c66156346cf364d158d6e30aa4d9"
},
{
"fixed": "8b611c9f4bd2d1615ef855cdf1459da3196d4d3c"
},
{
"introduced": "1929eeadf9b2bac12c5434fb56884ef27370580e"
},
{
"fixed": "a509158b1b1e21c892a7f1dacbe0d158076dc7b8"
},
{
"fixed": "df9e7f4c0afd311a672705f020d301efad355745"
},
{
"fixed": "edf1fbc7217aaf736955d2e13c9534901a2e0778"
}
],
"database_specific": {
"extracted_events": [
{
"cpe": "cpe:2.3:a:broadcom:rabbitmq_server:*:*:*:*:*:*:*:*",
"range": [
{
"introduced": "4.2.0"
},
{
"fixed": "4.2.8"
}
],
"source": "CPE_RANGE"
},
{
"cpe": "cpe:2.3:a:broadcom:rabbitmq_server:*:*:*:*:*:*:*:*",
"range": [
{
"introduced": "4.3.0"
},
{
"fixed": "4.3.2"
}
],
"source": "CPE_RANGE"
},
{
"range": [
{
"fixed": "df9e7f4c0afd311a672705f020d301efad355745"
}
],
"source": "REFERENCES_COMMIT"
},
{
"range": [
{
"fixed": "edf1fbc7217aaf736955d2e13c9534901a2e0778"
}
],
"source": "REFERENCES_COMMIT"
},
{
"range": [
{
"fixed": "8b611c9f4bd2d1615ef855cdf1459da3196d4d3c"
}
],
"source": "REFERENCES_TAG",
"original_tag": "v4.2.8"
},
{
"range": [
{
"fixed": "a509158b1b1e21c892a7f1dacbe0d158076dc7b8"
}
],
"source": "REFERENCES_TAG",
"original_tag": "v4.3.2"
}
]
}
}
],
"versions": [
"v4.2.7",
"v4.3.1",
"v4.2.6",
"v4.3.0",
"v4.2.5",
"v4.2.4",
"v4.2.3",
"v4.2.2",
"v4.2.1",
"v4.2.0"
],
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-67236.json"
}
}
],
"modified": "2026-10-28T02:30:52.517438499Z",
"provider": "osv",
"references": [
"https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.2.8",
"https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.3.2",
"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/67xxx/CVE-2026-67236.json",
"https://github.com/rabbitmq/rabbitmq-server/security/advisories/GHSA-88vh-gx85-p36m",
"https://nvd.nist.gov/vuln/detail/CVE-2026-67236",
"https://github.com/rabbitmq/rabbitmq-server/commit/df9e7f4c0afd311a672705f020d301efad355745",
"https://github.com/rabbitmq/rabbitmq-server/commit/edf1fbc7217aaf736955d2e13c9534901a2e0778"
],
"provider_metadata": {
"cwe_ids": [
"CWE-312"
],
"cna_assigner": "GitHub_M",
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/67xxx/CVE-2026-67236.json"
}
},
"related_cves": [
{
"value": "CVE-2026-67236",
"evidence": "/id"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 521117,
"published_at": "2026-09-25T15:59:10.275+00:00"
}