{
  "cveId": "CVE-2026-6253",
  "url": "https://patchblox.com/security/cve/CVE-2026-6253",
  "summary": "CVE-2026-6253 is fixed in 10 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: Routine.",
  "title": "proxy credentials leak over redirect-to proxy",
  "description": "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 \u0060http://\u0060), curl is asked to follow    a redirect to a URL using another scheme (say \u0060https://\u0060), accessed using a    second, different, proxy",
  "published": "2026-04-29T00:00:00Z",
  "severity": "Moderate",
  "cvss": 6.5,
  "cvssVector": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N",
  "epss": 0.00719,
  "epssPercentile": 0.54148,
  "priority": "Routine",
  "priorityTier": 4,
  "exploited": false,
  "vendorExploited": false,
  "disclosed": false,
  "vendorAdvisory": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-6253",
  "fixes": [
    {
      "platform": "linux",
      "product": "curl",
      "release": "Debian 13.5 (trixie)",
      "fixedVersion": "8.14.1-2\u002Bdeb13u4",
      "fix": "DEBIAN-CVE-2026-6253",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2026-6253",
      "released": "2026-05-15T16:01:09Z"
    },
    {
      "platform": "linux",
      "product": "curl",
      "release": "Debian 14",
      "fixedVersion": "8.20.0~rc3-1",
      "fix": "DEBIAN-CVE-2026-6253",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2026-6253",
      "released": "2026-05-15T16:01:09Z"
    },
    {
      "platform": "linux",
      "product": "curl",
      "release": "RHEL 10",
      "fixedVersion": "8.12.1-4.el10_2.7",
      "fix": "RHSA-2026:80512",
      "url": "https://patchblox.com/security/fix/linux/rhsa-2026-80512",
      "released": "2026-07-03T06:11:15Z"
    },
    {
      "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": "almalinux 10",
      "fixedVersion": "8.12.1-4.el10_2.7",
      "fix": "ALSA-2026:80512",
      "url": "https://patchblox.com/security/fix/linux/alsa-2026-80512",
      "released": "2026-11-07T00:39:57Z"
    },
    {
      "platform": "linux",
      "product": "curl",
      "release": "ol 10",
      "fixedVersion": "0:8.12.1-4.el10_2.7",
      "fix": "ELSA-2026-80512",
      "url": "https://patchblox.com/security/fix/linux/elsa-2026-80512",
      "released": "2026-11-07T00:59:15Z"
    },
    {
      "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": "rocky 10",
      "fixedVersion": "0:8.12.1-4.el10_2.7",
      "fix": "RLSA-2026:80512",
      "url": "https://patchblox.com/security/fix/linux/rlsa-2026-80512",
      "released": "2026-11-07T00:39:51Z"
    },
    {
      "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": "libcurl",
      "release": "almalinux 10",
      "fixedVersion": "8.12.1-4.el10_2.7",
      "fix": "ALSA-2026:80512",
      "url": "https://patchblox.com/security/fix/linux/alsa-2026-80512",
      "released": "2026-11-07T00:39:57Z"
    },
    {
      "platform": "linux",
      "product": "libcurl",
      "release": "ol 10",
      "fixedVersion": "0:8.12.1-4.el10_2.7",
      "fix": "ELSA-2026-80512",
      "url": "https://patchblox.com/security/fix/linux/elsa-2026-80512",
      "released": "2026-11-07T00:59:15Z"
    },
    {
      "platform": "linux",
      "product": "libcurl-devel",
      "release": "almalinux 10",
      "fixedVersion": "8.12.1-4.el10_2.7",
      "fix": "ALSA-2026:80512",
      "url": "https://patchblox.com/security/fix/linux/alsa-2026-80512",
      "released": "2026-11-07T00:39:57Z"
    },
    {
      "platform": "linux",
      "product": "libcurl-devel",
      "release": "ol 10",
      "fixedVersion": "0:8.12.1-4.el10_2.7",
      "fix": "ELSA-2026-80512",
      "url": "https://patchblox.com/security/fix/linux/elsa-2026-80512",
      "released": "2026-11-07T00:59:15Z"
    },
    {
      "platform": "linux",
      "product": "libcurl-minimal",
      "release": "almalinux 10",
      "fixedVersion": "8.12.1-4.el10_2.7",
      "fix": "ALSA-2026:80512",
      "url": "https://patchblox.com/security/fix/linux/alsa-2026-80512",
      "released": "2026-11-07T00:39:57Z"
    },
    {
      "platform": "linux",
      "product": "libcurl-minimal",
      "release": "ol 10",
      "fixedVersion": "0:8.12.1-4.el10_2.7",
      "fix": "ELSA-2026-80512",
      "url": "https://patchblox.com/security/fix/linux/elsa-2026-80512",
      "released": "2026-11-07T00:59:15Z"
    },
    {
      "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": "2026-11-08T13:06:02Z",
  "attribution": {
    "text": "Data: Patchblox Patch Radar",
    "url": "https://patchblox.com/security/patch-radar",
    "terms": "https://patchblox.com/security/patch-radar/use-the-data"
  }
}