cve-2026-55766

{
  "document": {
    "category": "csaf_vex",
    "csaf_version": "2.0",
    "distribution": {
      "text": "Copyright © Red Hat, Inc. All rights reserved.",
      "tlp": {
        "label": "WHITE",
        "url": "https://www.first.org/tlp/"
      }
    },
    "lang": "en",
    "notes": [
      {
        "category": "legal_disclaimer",
        "text": "This content is licensed under the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/). If you distribute this content, or a modified version of it, you must provide attribution to Red Hat Inc. and provide a link to the original.",
        "title": "Terms of Use"
      }
    ],
    "publisher": {
      "category": "vendor",
      "contact_details": "https://access.redhat.com/security/team/contact/",
      "issuing_authority": "Red Hat Product Security is responsible for vulnerability handling across all Red Hat products and services.",
      "name": "Red Hat Product Security",
      "namespace": "https://www.redhat.com"
    },
    "references": [
      {
        "category": "self",
        "summary": "Canonical URL",
        "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-55766.json"
      }
    ],
    "title": "guzzlehttp/psr7: guzzlehttp/psr7: Information disclosure due to improper handling of CR/LF characters in HTTP start-line fields",
    "tracking": {
      "current_release_date": "2026-06-28T07:14:30+00:00",
      "generator": {
        "date": "2026-06-28T07:14:30+00:00",
        "engine": {
          "name": "Red Hat SDEngine",
          "version": "5.2.6"
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      },
      "id": "CVE-2026-55766",
      "initial_release_date": "2026-06-23T15:07:36.413000+00:00",
      "revision_history": [
        {
          "date": "2026-06-23T15:07:36.413000+00:00",
          "number": "1",
          "summary": "Initial version"
        },
        {
          "date": "2026-06-23T19:53:34.614278+00:00",
          "number": "2",
          "summary": "Current version"
        },
        {
          "date": "2026-06-28T07:14:30+00:00",
          "number": "3",
          "summary": "Last generated version"
        }
      ],
      "status": "final",
      "version": "3"
    }
  },
  "product_tree": {
    "branches": [
      {
        "category": "vendor",
        "name": "Red Hat",
        "product": {
          "name": "All currently supported Red Hat products",
          "product_id": "red_hat_products",
          "product_identification_helper": {
            "cpe": "cpe:/a:redhat"
          }
        }
      }
    ]
  },
  "vulnerabilities": [
    {
      "cve": "CVE-2026-55766",
      "discovery_date": "2026-06-23T16:01:06.839408+00:00",
      "flags": [
        {
          "label": "vulnerable_code_not_present",
          "product_ids": [
            "red_hat_products"
          ]
        }
      ],
      "notes": [
        {
          "category": "description",
          "text": "A flaw was found in guzzlehttp/psr7, a PHP library for HTTP messages. This vulnerability allows a remote attacker to inject arbitrary header lines into serialized HTTP/1.x messages. The flaw stems from the library's failure to reject carriage return (CR) and line feed (LF) characters in HTTP start-line fields. This could lead to information disclosure or manipulation of HTTP headers if an application processes attacker-controlled data in these fields and then serializes the message.",
          "title": "Vulnerability description"
        },
        {
          "category": "other",
          "text": "Red Hat Product Security has determined that this vulnerability does not affect any currently supported Red Hat product. This assessment may evolve based on further analysis and discovery. For more information about this vulnerability and the products it affects, please see the linked references.",
          "title": "Statement"
        },
        {
          "category": "general",
          "text": "The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.",
          "title": "CVSS score applicability"
        }
      ],
      "product_status": {
        "known_not_affected": [
          "red_hat_products"
        ]
      },
      "references": [
        {
          "category": "self",
          "summary": "Canonical URL",
          "url": "https://access.redhat.com/security/cve/CVE-2026-55766"
        },
        {
          "category": "external",
          "summary": "https://www.cve.org/CVERecord?id=CVE-2026-55766",
          "url": "https://www.cve.org/CVERecord?id=CVE-2026-55766"
        }
      ],
      "release_date": "2026-06-23T15:07:36.413000+00:00",
      "scores": [
        {
          "cvss_v3": {
            "attackComplexity": "HIGH",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 4.8,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "LOW",
            "integrityImpact": "LOW",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N",
            "version": "3.1"
          },
          "products": [
            "red_hat_products"
          ]
        }
      ],
      "title": "guzzlehttp/psr7: guzzlehttp/psr7: Information disclosure due to improper handling of CR/LF characters in HTTP start-line fields"
    }
  ]
}