{
  "cveId": "CVE-2026-6276",
  "url": "https://patchblox.com/security/cve/CVE-2026-6276",
  "summary": "CVE-2026-6276 is fixed in 7 products on 1 platform, first by curl 8.18.0-1ubuntu2.1, released April 29, 2026. It is not reported as exploited. Patch Radar priority: High.",
  "title": "stale custom cookie host causes cookie leak",
  "description": "Using libcurl, when a custom \u0060Host:\u0060 header is first set for an HTTP request and a second request is subsequently done using the same *easy handle* but without the custom \u0060Host:\u0060 header set, the second request would use stale information and pass on cookies meant for the first host in the second request. Leak them.",
  "published": "2026-04-29T07:00:00Z",
  "severity": "Moderate",
  "cvss": 7.5,
  "cvssVector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
  "epss": 0.00295,
  "epssPercentile": 0.2227,
  "priority": "High",
  "priorityTier": 3,
  "exploited": false,
  "vendorExploited": false,
  "disclosed": false,
  "vendorAdvisory": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-6276",
  "fixes": [
    {
      "platform": "linux",
      "product": "curl",
      "release": "Debian 13.5 (trixie)",
      "fixedVersion": "8.14.1-2\u002Bdeb13u4",
      "fix": "DEBIAN-CVE-2026-6276",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2026-6276",
      "released": "2026-05-15T16:01:09Z"
    },
    {
      "platform": "linux",
      "product": "curl",
      "release": "Debian 14",
      "fixedVersion": "8.20.0~rc3-1",
      "fix": "DEBIAN-CVE-2026-6276",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2026-6276",
      "released": "2026-05-15T16:01:09Z"
    },
    {
      "platform": "linux",
      "product": "curl",
      "release": "Ubuntu 22.04.1 LTS (jammy)",
      "fixedVersion": "7.81.0-1ubuntu1.24",
      "fix": "curl 7.81.0-1ubuntu1.24",
      "url": "https://patchblox.com/security/fix/linux/ubuntu-jammy-curl-7.81.0-1ubuntu1.24",
      "released": "2026-05-15T16:01:26Z"
    },
    {
      "platform": "linux",
      "product": "curl",
      "release": "Ubuntu 24.04.5 LTS (noble)",
      "fixedVersion": "8.5.0-2ubuntu10.9",
      "fix": "curl 8.5.0-2ubuntu10.9",
      "url": "https://patchblox.com/security/fix/linux/ubuntu-noble-curl-8.5.0-2ubuntu10.9",
      "released": "2026-05-15T16:01:30Z"
    },
    {
      "platform": "linux",
      "product": "curl",
      "release": "Ubuntu 25.10 (questing)",
      "fixedVersion": "8.14.1-2ubuntu1.3",
      "fix": "curl 8.14.1-2ubuntu1.3",
      "url": "https://patchblox.com/security/fix/linux/ubuntu-questing-curl-8.14.1-2ubuntu1.3",
      "released": "2026-05-15T16:01:35Z"
    },
    {
      "platform": "linux",
      "product": "curl",
      "release": "Ubuntu 26.04.1 LTS (resolute)",
      "fixedVersion": "8.18.0-1ubuntu2.1",
      "fix": "curl 8.18.0-1ubuntu2.1",
      "url": "https://patchblox.com/security/fix/linux/ubuntu-resolute-curl-8.18.0-1ubuntu2.1",
      "released": "2026-04-29T07:00:00Z"
    },
    {
      "platform": "linux",
      "product": "curl",
      "release": "opensuse-leap 16.0",
      "fixedVersion": "8.14.1-160000.6.1",
      "fix": "OPENSUSE-SU-2026:20973-1",
      "url": "https://patchblox.com/security/fix/linux/opensuse-su-2026-20973-1",
      "released": "2026-06-17T08:47:34Z"
    },
    {
      "platform": "linux",
      "product": "curl",
      "release": "sles 15.7",
      "fixedVersion": "8.14.1-150700.7.23.1",
      "fix": "SUSE-SU-2026:3798-1",
      "url": "https://patchblox.com/security/fix/linux/suse-su-2026-3798-1",
      "released": "2026-08-25T12:41:04Z"
    },
    {
      "platform": "linux",
      "product": "curl",
      "release": "sles 16.0",
      "fixedVersion": "8.14.1-160000.6.1",
      "fix": "SUSE-SU-2026:22156-1",
      "url": "https://patchblox.com/security/fix/linux/suse-su-2026-22156-1",
      "released": "2026-06-17T08:57:16Z"
    },
    {
      "platform": "linux",
      "product": "curl-mini",
      "release": "sles 16.0",
      "fixedVersion": "8.14.1-160000.6.1",
      "fix": "SUSE-SU-2026:22156-1",
      "url": "https://patchblox.com/security/fix/linux/suse-su-2026-22156-1",
      "released": "2026-06-17T08:57:16Z"
    },
    {
      "platform": "linux",
      "product": "libcurl3-gnutls",
      "release": "Ubuntu 22.04.1 LTS (jammy)",
      "fixedVersion": "7.81.0-1ubuntu1.24",
      "fix": "libcurl3-gnutls 7.81.0-1ubuntu1.24",
      "url": "https://patchblox.com/security/fix/linux/ubuntu-jammy-libcurl3-gnutls-7.81.0-1ubuntu1.24",
      "released": "2026-05-15T16:01:26Z"
    },
    {
      "platform": "linux",
      "product": "libcurl3-nss",
      "release": "Ubuntu 22.04.1 LTS (jammy)",
      "fixedVersion": "7.81.0-1ubuntu1.24",
      "fix": "libcurl3-nss 7.81.0-1ubuntu1.24",
      "url": "https://patchblox.com/security/fix/linux/ubuntu-jammy-libcurl3-nss-7.81.0-1ubuntu1.24",
      "released": "2026-05-15T16:01:26Z"
    },
    {
      "platform": "linux",
      "product": "libcurl3t64-gnutls",
      "release": "Ubuntu 24.04.5 LTS (noble)",
      "fixedVersion": "8.5.0-2ubuntu10.9",
      "fix": "libcurl3t64-gnutls 8.5.0-2ubuntu10.9",
      "url": "https://patchblox.com/security/fix/linux/ubuntu-noble-libcurl3t64-gnutls-8.5.0-2ubuntu10.9",
      "released": "2026-05-15T16:01:30Z"
    },
    {
      "platform": "linux",
      "product": "libcurl3t64-gnutls",
      "release": "Ubuntu 25.10 (questing)",
      "fixedVersion": "8.14.1-2ubuntu1.3",
      "fix": "libcurl3t64-gnutls 8.14.1-2ubuntu1.3",
      "url": "https://patchblox.com/security/fix/linux/ubuntu-questing-libcurl3t64-gnutls-8.14.1-2ubuntu1.3",
      "released": "2026-05-15T16:01:35Z"
    },
    {
      "platform": "linux",
      "product": "libcurl3t64-gnutls",
      "release": "Ubuntu 26.04.1 LTS (resolute)",
      "fixedVersion": "8.18.0-1ubuntu2.1",
      "fix": "libcurl3t64-gnutls 8.18.0-1ubuntu2.1",
      "url": "https://patchblox.com/security/fix/linux/ubuntu-resolute-libcurl3t64-gnutls-8.18.0-1ubuntu2.1",
      "released": "2026-04-29T07:00:00Z"
    },
    {
      "platform": "linux",
      "product": "libcurl4",
      "release": "Ubuntu 22.04.1 LTS (jammy)",
      "fixedVersion": "7.81.0-1ubuntu1.24",
      "fix": "libcurl4 7.81.0-1ubuntu1.24",
      "url": "https://patchblox.com/security/fix/linux/ubuntu-jammy-libcurl4-7.81.0-1ubuntu1.24",
      "released": "2026-05-15T16:01:26Z"
    },
    {
      "platform": "linux",
      "product": "libcurl4t64",
      "release": "Ubuntu 24.04.5 LTS (noble)",
      "fixedVersion": "8.5.0-2ubuntu10.9",
      "fix": "libcurl4t64 8.5.0-2ubuntu10.9",
      "url": "https://patchblox.com/security/fix/linux/ubuntu-noble-libcurl4t64-8.5.0-2ubuntu10.9",
      "released": "2026-05-15T16:01:30Z"
    },
    {
      "platform": "linux",
      "product": "libcurl4t64",
      "release": "Ubuntu 25.10 (questing)",
      "fixedVersion": "8.14.1-2ubuntu1.3",
      "fix": "libcurl4t64 8.14.1-2ubuntu1.3",
      "url": "https://patchblox.com/security/fix/linux/ubuntu-questing-libcurl4t64-8.14.1-2ubuntu1.3",
      "released": "2026-05-15T16:01:35Z"
    },
    {
      "platform": "linux",
      "product": "libcurl4t64",
      "release": "Ubuntu 26.04.1 LTS (resolute)",
      "fixedVersion": "8.18.0-1ubuntu2.1",
      "fix": "libcurl4t64 8.18.0-1ubuntu2.1",
      "url": "https://patchblox.com/security/fix/linux/ubuntu-resolute-libcurl4t64-8.18.0-1ubuntu2.1",
      "released": "2026-04-29T07:00:00Z"
    }
  ],
  "noFixYet": [],
  "dataAsOf": "2026-11-08T19:12:23Z",
  "attribution": {
    "text": "Data: Patchblox Patch Radar",
    "url": "https://patchblox.com/security/patch-radar",
    "terms": "https://patchblox.com/security/patch-radar/use-the-data"
  }
}