CVE-2026-55767
Guzzle is an extensible PHP HTTP client. Prior to 7.12.1, CookieJar incorrectly accepts cookies with a dot-only Domain attribute and whitespace-padded variants. SetCookie::matchesDomain() removes leading dots from the cookie domain, normalizing dot-only values to the empty string; SetCookie::validate() only rejected a strictly empty domain, so these cookies could be stored and the empty normalized domain was treated as matching any request host.
Leer descripción completaMostrar menos
An attacker-controlled origin that an application requests with a shared cookie jar can therefore set a cookie that Guzzle later sends to unrelated hosts using the same jar. This may allow cookie injection or session fixation against downstream services, depending on how those services interpret the injected cookie. This vulnerability is fixed in 7.12.1.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N
- Puntuación base: 5.8
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.21%
- Percentil entre todas las CVEs puntuadas: 10
- 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-346, CWE-1286
Referencias
- https://github.com/FriendsOfPHP/security-advisories/blob/master/guzzlehttp/guzzle/CVE-2026-55767.yaml
- https://github.com/guzzle/guzzle/commit/7f537cded1912349abf5081258d6db19106d774d
- https://github.com/guzzle/guzzle/pull/3653
- https://github.com/guzzle/guzzle/releases/tag/7.12.1
- https://github.com/guzzle/guzzle/security/advisories/GHSA-cwxw-98qj-8qjx
JSON original (NVD)
Mostrar
{
"id": "CVE-2026-55767",
"cveTags": [],
"metrics": {
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"id": "CVE-2026-55767",
"role": "CISA Coordinator",
"options": [
{
"exploitation": "none"
},
{
"automatable": "yes"
},
{
"technicalImpact": "partial"
}
],
"version": "2.0.3",
"timestamp": "2026-06-23T17:47:47.323538Z"
}
}
],
"cvssMetricV31": [
{
"type": "Secondary",
"source": "security-advisories@github.com",
"cvssData": {
"scope": "CHANGED",
"version": "3.1",
"baseScore": 5.8,
"attackVector": "NETWORK",
"baseSeverity": "MEDIUM",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N",
"integrityImpact": "LOW",
"userInteraction": "NONE",
"attackComplexity": "LOW",
"availabilityImpact": "NONE",
"privilegesRequired": "NONE",
"confidentialityImpact": "NONE"
},
"impactScore": 1.4,
"exploitabilityScore": 3.9
}
]
},
"affected": [
{
"source": "security-advisories@github.com",
"affectedData": [
{
"vendor": "guzzle",
"product": "guzzle",
"versions": [
{
"status": "affected",
"version": "< 7.12.1"
}
]
}
]
}
],
"published": "2026-06-23T16:17:03.263",
"references": [
{
"url": "https://github.com/FriendsOfPHP/security-advisories/blob/master/guzzlehttp/guzzle/CVE-2026-55767.yaml",
"source": "security-advisories@github.com"
},
{
"url": "https://github.com/guzzle/guzzle/commit/7f537cded1912349abf5081258d6db19106d774d",
"source": "security-advisories@github.com"
},
{
"url": "https://github.com/guzzle/guzzle/pull/3653",
"source": "security-advisories@github.com"
},
{
"url": "https://github.com/guzzle/guzzle/releases/tag/7.12.1",
"source": "security-advisories@github.com"
},
{
"url": "https://github.com/guzzle/guzzle/security/advisories/GHSA-cwxw-98qj-8qjx",
"tags": [
"Third Party Advisory"
],
"source": "security-advisories@github.com"
}
],
"vulnStatus": "Modified",
"weaknesses": [
{
"type": "Secondary",
"source": "security-advisories@github.com",
"description": [
{
"lang": "en",
"value": "CWE-346"
},
{
"lang": "en",
"value": "CWE-1286"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "Guzzle is an extensible PHP HTTP client. Prior to 7.12.1, CookieJar incorrectly accepts cookies with a dot-only Domain attribute and whitespace-padded variants. SetCookie::matchesDomain() removes leading dots from the cookie domain, normalizing dot-only values to the empty string; SetCookie::validate() only rejected a strictly empty domain, so these cookies could be stored and the empty normalized domain was treated as matching any request host. An attacker-controlled origin that an application requests with a shared cookie jar can therefore set a cookie that Guzzle later sends to unrelated hosts using the same jar. This may allow cookie injection or session fixation against downstream services, depending on how those services interpret the injected cookie. This vulnerability is fixed in 7.12.1."
}
],
"lastModified": "2026-08-05T22:17:07.543",
"configurations": [
{
"nodes": [
{
"negate": false,
"cpeMatch": [
{
"criteria": "cpe:2.3:a:guzzlephp:guzzle:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "F4DA5939-7C26-4452-A790-9A0457E04DE4",
"versionEndExcluding": "7.12.1"
}
],
"operator": "OR"
}
]
}
],
"sourceIdentifier": "security-advisories@github.com"
}