CVE-2026-6253
Estado: ModificadaMedia (5.9)—
curl might erroneously pass on credentials for a first proxy to a second proxy.
This can happen when the following conditions are true:
1. curl is setup to use specific different proxies for different URL schemes 2. the first proxy needs credentials 3. the second proxy uses no credentials 4. while using the first proxy (using say `http://`), curl is asked to follow a redirect to a URL using another scheme (say `https://`), accessed using a second, different, proxy
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
- Puntuación base: 5.9
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.75%
- Percentil entre todas las CVEs puntuadas: 53
- Fecha de la puntuación: 5/10/2026
EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).
Tecnologías afectadas (1)
CWE
- CWE-522
- CWE-522
Referencias
JSON original (NVD)
Mostrar
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"published": "2026-05-13T13:01:56.570",
"references": [
{
"url": "https://curl.se/docs/CVE-2026-6253.html",
"tags": [
"Patch",
"Vendor Advisory"
],
"source": "2499f714-1537-4658-8207-48ae4bb9eae9"
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{
"url": "https://curl.se/docs/CVE-2026-6253.json",
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"source": "2499f714-1537-4658-8207-48ae4bb9eae9"
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{
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"Third Party Advisory"
],
"source": "2499f714-1537-4658-8207-48ae4bb9eae9"
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{
"url": "http://www.openwall.com/lists/oss-security/2026/04/29/11",
"tags": [
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"source": "af854a3a-2127-422b-91ae-364da2661108"
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{
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"tags": [
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"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"
}
],
"vulnStatus": "Modified",
"weaknesses": [
{
"type": "Secondary",
"source": "2499f714-1537-4658-8207-48ae4bb9eae9",
"description": [
{
"lang": "en",
"value": "CWE-522"
}
]
},
{
"type": "Primary",
"source": "nvd@nist.gov",
"description": [
{
"lang": "en",
"value": "CWE-522"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "curl might erroneously pass on credentials for a first proxy to a second\nproxy.\n\nThis can happen when the following conditions are true:\n\n1. curl is setup to use specific different proxies for different URL schemes\n2. the first proxy needs credentials\n3. the second proxy uses no credentials\n4. while using the first proxy (using say `http://`), curl is asked to follow\n a redirect to a URL using another scheme (say `https://`), accessed using a\n second, different, proxy"
}
],
"lastModified": "2026-09-15T07:16:29.073",
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{
"negate": false,
"cpeMatch": [
{
"criteria": "cpe:2.3:a:haxx:curl:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "C839F5FA-8CCE-4F13-851D-E60E8EAAA08C",
"versionEndExcluding": "8.20.0",
"versionStartIncluding": "7.14.1"
}
],
"operator": "OR"
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}
],
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}