UBUNTU-CVE-2026-86410 (CVE-2026-86410)

Vulnerability from osv_ubuntu – Published: 2026-10-14 06:00 – Updated: 2026-10-14 06:00 – Source website
VLAI
Details

A flaw in the curl command line tool's logic makes it only set SSH host verification options when interacting directly using SFTP or SCP, and not as a result of following a redirect. This means --knownhosts, --hostpubsha256, and --hostpubmd5 are never installed when the initial URL is HTTPS. If --location and --proto-redir +sftp is used and the server returns a Location: sftp://example.com redirect, the SFTP connection proceeds without any of the user's requested SSH host verification methods.

Severity
N/A (UNKNOWN)
low
References
To clipboard 

{
  "affected": [
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "curl",
            "binary_version": "8.20.0-2ubuntu11"
          },
          {
            "binary_name": "libcurl3t64-gnutls",
            "binary_version": "8.20.0-2ubuntu11"
          },
          {
            "binary_name": "libcurl4t64",
            "binary_version": "8.20.0-2ubuntu11"
          }
        ],
        "priority_reason": "Upstream defined this as low severity"
      },
      "package": {
        "ecosystem": "Ubuntu:26.10",
        "name": "curl",
        "purl": "pkg:deb/ubuntu/curl@8.20.0-2ubuntu11?arch=source\u0026distro=stonking"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "8.18.0-1ubuntu2",
        "8.20.0-2ubuntu1",
        "8.20.0-2ubuntu3",
        "8.20.0-2ubuntu10",
        "8.20.0-2ubuntu11"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "curl",
            "binary_version": "8.18.0-1ubuntu2.8"
          },
          {
            "binary_name": "libcurl3t64-gnutls",
            "binary_version": "8.18.0-1ubuntu2.8"
          },
          {
            "binary_name": "libcurl4t64",
            "binary_version": "8.18.0-1ubuntu2.8"
          }
        ],
        "priority_reason": "Upstream defined this as low severity"
      },
      "package": {
        "ecosystem": "Ubuntu:26.04:LTS",
        "name": "curl",
        "purl": "pkg:deb/ubuntu/curl@8.18.0-1ubuntu2.8?arch=source\u0026distro=resolute"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "8.18.0-1ubuntu2.8"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "8.14.1-2ubuntu1",
        "8.17.0-1ubuntu1",
        "8.18.0-1ubuntu1",
        "8.18.0-1ubuntu2",
        "8.18.0-1ubuntu2.1",
        "8.18.0-1ubuntu2.2",
        "8.18.0-1ubuntu2.3",
        "8.18.0-1ubuntu2.4",
        "8.18.0-1ubuntu2.5",
        "8.18.0-1ubuntu2.7"
      ]
    }
  ],
  "aliases": [],
  "details": "A flaw in the curl command line tool\u0027s logic makes it only set SSH host verification options when interacting directly using SFTP or SCP, and not as a result of following a redirect. This means `--knownhosts`, `--hostpubsha256`, and `--hostpubmd5` are never installed when the initial URL is HTTPS. If `--location` and `--proto-redir +sftp` is used and the server returns a `Location: sftp://example.com` redirect, the SFTP connection proceeds without any of the user\u0027s requested SSH host verification methods.",
  "id": "UBUNTU-CVE-2026-86410",
  "modified": "2026-10-14T06:00:00Z",
  "published": "2026-10-14T06:00:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-86410"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-86410"
    },
    {
      "type": "REPORT",
      "url": "https://curl.se/docs/CVE-2026-86410.html"
    },
    {
      "type": "ADVISORY",
      "url": "https://ubuntu.com/security/notices/USN-8927-1"
    }
  ],
  "related": [
    "USN-8927-1"
  ],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "low",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2026-86410"
  ]
}



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