CVE-2026-6019 (GCVE-0-2026-6019)
Vulnerability from cvelistv5
Published
2026-04-22 19:28
Modified
2026-06-10 18:58
Severity ?
VLAI Severity ?
EPSS score ?
CWE
- CWE-150 - Improper neutralization of escape, meta, or control sequences
Summary
http.cookies.Morsel.js_output() returns an inline <script> snippet and only escapes " for JavaScript string context. It does not neutralize the HTML parser-sensitive sequence </script> inside the generated script element. Mitigation base64-encodes the cookie value to disallow escaping using cookie value.
References
Impacted products
| Vendor | Product | Version | ||
|---|---|---|---|---|
| Python Software Foundation | CPython |
Version: 0 Version: 3.14.0a1 Version: 3.15.0a1 |
{
"containers": {
"adp": [
{
"metrics": [
{
"other": {
"content": {
"id": "CVE-2026-6019",
"options": [
{
"Exploitation": "none"
},
{
"Automatable": "no"
},
{
"Technical Impact": "partial"
}
],
"role": "CISA Coordinator",
"timestamp": "2026-04-22T20:02:17.071906Z",
"version": "2.0.3"
},
"type": "ssvc"
}
}
],
"providerMetadata": {
"dateUpdated": "2026-04-22T20:02:34.468Z",
"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"shortName": "CISA-ADP"
},
"title": "CISA ADP Vulnrichment"
}
],
"cna": {
"affected": [
{
"defaultStatus": "unaffected",
"product": "CPython",
"repo": "https://github.com/python/cpython",
"vendor": "Python Software Foundation",
"versions": [
{
"lessThan": "3.13.14",
"status": "affected",
"version": "0",
"versionType": "python"
},
{
"lessThan": "3.14.5rc1",
"status": "affected",
"version": "3.14.0a1",
"versionType": "python"
},
{
"lessThan": "3.15.0b1",
"status": "affected",
"version": "3.15.0a1",
"versionType": "python"
}
]
}
],
"credits": [
{
"lang": "en",
"type": "reporter",
"value": "oolongeya (https://github.com/komi22)"
},
{
"lang": "en",
"type": "coordinator",
"value": "Seth Larson (https://github.com/sethmlarson)"
}
],
"descriptions": [
{
"lang": "en",
"supportingMedia": [
{
"base64": false,
"type": "text/html",
"value": "\u003ccode\u003ehttp.cookies.Morsel.js_output()\u003c/code\u003e returns an inline \u003ccode\u003e\u0026lt;script\u0026gt;\u003c/code\u003e snippet and only escapes \u003ccode\u003e\"\u003c/code\u003e for JavaScript string context. It does not neutralize the HTML parser-sensitive sequence \u003ccode\u003e\u0026lt;/script\u0026gt;\u003c/code\u003e inside the generated script element. Mitigation base64-encodes the cookie value to disallow escaping using cookie value."
}
],
"value": "http.cookies.Morsel.js_output() returns an inline \u003cscript\u003e snippet and only escapes \" for JavaScript string context. It does not neutralize the HTML parser-sensitive sequence \u003c/script\u003e inside the generated script element. Mitigation base64-encodes the cookie value to disallow escaping using cookie value."
}
],
"metrics": [
{
"cvssV4_0": {
"Automatable": "NOT_DEFINED",
"Recovery": "NOT_DEFINED",
"Safety": "NOT_DEFINED",
"attackComplexity": "LOW",
"attackRequirements": "PRESENT",
"attackVector": "NETWORK",
"baseScore": 2.1,
"baseSeverity": "LOW",
"exploitMaturity": "NOT_DEFINED",
"privilegesRequired": "HIGH",
"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:H/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N",
"version": "4.0",
"vulnAvailabilityImpact": "NONE",
"vulnConfidentialityImpact": "LOW",
"vulnIntegrityImpact": "LOW",
"vulnerabilityResponseEffort": "NOT_DEFINED"
},
"format": "CVSS",
"scenarios": [
{
"lang": "en",
"value": "GENERAL"
}
]
}
],
"problemTypes": [
{
"descriptions": [
{
"cweId": "CWE-150",
"description": "CWE-150 Improper neutralization of escape, meta, or control sequences",
"lang": "en",
"type": "CWE"
}
]
}
],
"providerMetadata": {
"dateUpdated": "2026-06-10T18:58:07.798Z",
"orgId": "28c92f92-d60d-412d-b760-e73465c3df22",
"shortName": "PSF"
},
"references": [
{
"tags": [
"patch"
],
"url": "https://github.com/python/cpython/pull/148848"
},
{
"tags": [
"issue-tracking"
],
"url": "https://github.com/python/cpython/issues/90309"
},
{
"tags": [
"vendor-advisory"
],
"url": "https://mail.python.org/archives/list/security-announce@python.org/thread/IVNWGV2BBNC3RHQAFS22UP4DY56SAXX3/"
},
{
"tags": [
"patch"
],
"url": "https://github.com/python/cpython/commit/76b3923d688c0efc580658476c5f525ec8735104"
},
{
"tags": [
"patch"
],
"url": "https://github.com/python/cpython/commit/3c59b8b53fc75c7f9578d16fb8201ceb43e8f76c"
},
{
"tags": [
"patch"
],
"url": "https://github.com/python/cpython/commit/f795e042043dfe26c42e1971d4502c1cdc4c65b8"
}
],
"source": {
"discovery": "UNKNOWN"
},
"title": "BaseCookie.js_output() does not neutralize embedded characters",
"x_generator": {
"engine": "Vulnogram 0.6.0"
}
}
},
"cveMetadata": {
"assignerOrgId": "28c92f92-d60d-412d-b760-e73465c3df22",
"assignerShortName": "PSF",
"cveId": "CVE-2026-6019",
"datePublished": "2026-04-22T19:28:08.720Z",
"dateReserved": "2026-04-09T15:35:00.668Z",
"dateUpdated": "2026-06-10T18:58:07.798Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2",
"vulnerability-lookup:meta": {
"vulnrichment": {
"containers": "{\"adp\": [{\"title\": \"CISA ADP Vulnrichment\", \"metrics\": [{\"other\": {\"type\": \"ssvc\", \"content\": {\"id\": \"CVE-2026-6019\", \"role\": \"CISA Coordinator\", \"options\": [{\"Exploitation\": \"none\"}, {\"Automatable\": \"no\"}, {\"Technical Impact\": \"partial\"}], \"version\": \"2.0.3\", \"timestamp\": \"2026-04-22T20:02:17.071906Z\"}}}], \"providerMetadata\": {\"orgId\": \"134c704f-9b21-4f2e-91b3-4a467353bcc0\", \"shortName\": \"CISA-ADP\", \"dateUpdated\": \"2026-04-22T20:02:21.519Z\"}}], \"cna\": {\"title\": \"BaseCookie.js_output() does not neutralize embedded characters\", \"source\": {\"discovery\": \"UNKNOWN\"}, \"credits\": [{\"lang\": \"en\", \"type\": \"reporter\", \"value\": \"oolongeya (https://github.com/komi22)\"}, {\"lang\": \"en\", \"type\": \"coordinator\", \"value\": \"Seth Larson (https://github.com/sethmlarson)\"}], \"metrics\": [{\"format\": \"CVSS\", \"cvssV4_0\": {\"Safety\": \"NOT_DEFINED\", \"version\": \"4.0\", \"Recovery\": \"NOT_DEFINED\", \"baseScore\": 2.1, \"Automatable\": \"NOT_DEFINED\", \"attackVector\": \"NETWORK\", \"baseSeverity\": \"LOW\", \"valueDensity\": \"NOT_DEFINED\", \"vectorString\": \"CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N\", \"exploitMaturity\": \"NOT_DEFINED\", \"providerUrgency\": \"NOT_DEFINED\", \"userInteraction\": \"NONE\", \"attackComplexity\": \"LOW\", \"attackRequirements\": \"PRESENT\", \"privilegesRequired\": \"HIGH\", \"subIntegrityImpact\": \"NONE\", \"vulnIntegrityImpact\": \"LOW\", \"subAvailabilityImpact\": \"NONE\", \"vulnAvailabilityImpact\": \"NONE\", \"subConfidentialityImpact\": \"NONE\", \"vulnConfidentialityImpact\": \"LOW\", \"vulnerabilityResponseEffort\": \"NOT_DEFINED\"}, \"scenarios\": [{\"lang\": \"en\", \"value\": \"GENERAL\"}]}], \"affected\": [{\"repo\": \"https://github.com/python/cpython\", \"vendor\": \"Python Software Foundation\", \"product\": \"CPython\", \"versions\": [{\"status\": \"affected\", \"version\": \"0\", \"lessThan\": \"3.15.0\", \"versionType\": \"python\"}], \"defaultStatus\": \"unaffected\"}], \"references\": [{\"url\": \"https://github.com/python/cpython/pull/148848\", \"tags\": [\"patch\"]}, {\"url\": \"https://github.com/python/cpython/issues/90309\", \"tags\": [\"issue-tracking\"]}, {\"url\": \"https://mail.python.org/archives/list/security-announce@python.org/thread/IVNWGV2BBNC3RHQAFS22UP4DY56SAXX3/\", \"tags\": [\"vendor-advisory\"]}, {\"url\": \"https://github.com/python/cpython/commit/76b3923d688c0efc580658476c5f525ec8735104\", \"tags\": [\"patch\"]}, {\"url\": \"https://github.com/python/cpython/commit/3c59b8b53fc75c7f9578d16fb8201ceb43e8f76c\", \"tags\": [\"patch\"]}, {\"url\": \"https://github.com/python/cpython/commit/f795e042043dfe26c42e1971d4502c1cdc4c65b8\", \"tags\": [\"patch\"]}], \"x_generator\": {\"engine\": \"Vulnogram 0.6.0\"}, \"descriptions\": [{\"lang\": \"en\", \"value\": \"http.cookies.Morsel.js_output() returns an inline \u003cscript\u003e snippet and only escapes \\\" for JavaScript string context. It does not neutralize the HTML parser-sensitive sequence \u003c/script\u003e inside the generated script element. Mitigation base64-encodes the cookie value to disallow escaping using cookie value.\", \"supportingMedia\": [{\"type\": \"text/html\", \"value\": \"\u003ccode\u003ehttp.cookies.Morsel.js_output()\u003c/code\u003e returns an inline \u003ccode\u003e\u0026lt;script\u0026gt;\u003c/code\u003e snippet and only escapes \u003ccode\u003e\\\"\u003c/code\u003e for JavaScript string context. It does not neutralize the HTML parser-sensitive sequence \u003ccode\u003e\u0026lt;/script\u0026gt;\u003c/code\u003e inside the generated script element. Mitigation base64-encodes the cookie value to disallow escaping using cookie value.\", \"base64\": false}]}], \"problemTypes\": [{\"descriptions\": [{\"lang\": \"en\", \"type\": \"CWE\", \"cweId\": \"CWE-150\", \"description\": \"CWE-150 Improper neutralization of escape, meta, or control sequences\"}]}], \"providerMetadata\": {\"orgId\": \"28c92f92-d60d-412d-b760-e73465c3df22\", \"shortName\": \"PSF\", \"dateUpdated\": \"2026-04-29T15:31:09.049Z\"}}}",
"cveMetadata": "{\"cveId\": \"CVE-2026-6019\", \"state\": \"PUBLISHED\", \"dateUpdated\": \"2026-04-29T15:31:09.049Z\", \"dateReserved\": \"2026-04-09T15:35:00.668Z\", \"assignerOrgId\": \"28c92f92-d60d-412d-b760-e73465c3df22\", \"datePublished\": \"2026-04-22T19:28:08.720Z\", \"assignerShortName\": \"PSF\"}",
"dataType": "CVE_RECORD",
"dataVersion": "5.2"
}
}
}
Loading…
Loading…
Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.
Loading…
Loading…