CVE-2026-86415

Full vulnerability record from the local CVENow database.

Description

libcurl's connection cache match function never considers the automatic client certificate option, so a cached, already authenticated Schannel connection can be handed to a transfer that got redirected to a different origin, even though the code explicitly switched off the auto client cert option for that transfer to prevent exactly this.

Severity

HIGH

CVSS score

7.5 (v3.1)

Vulnerability status

Awaiting Analysis

Source identifier

2499f714-1537-4658-8207-48ae4bb9eae9

Published

2026-10-20 21:17:20.067000

Last modified

2026-10-30 12:16:45.447000

View original CVE JSON

{
  "id": "CVE-2026-86415",
  "sourceIdentifier": "2499f714-1537-4658-8207-48ae4bb9eae9",
  "published": "2026-10-20T21:17:20.067",
  "lastModified": "2026-10-30T12:16:45.447",
  "vulnStatus": "Awaiting Analysis",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "libcurl's connection cache match function never considers the automatic client\ncertificate option, so a cached, already authenticated Schannel connection can\nbe handed to a transfer that got redirected to a different origin, even though\nthe code explicitly switched off the auto client cert option for that transfer\nto prevent exactly this."
    }
  ],
  "affected": [
    {
      "source": "2499f714-1537-4658-8207-48ae4bb9eae9",
      "affectedData": [
        {
          "vendor": "curl",
          "product": "curl",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "8.22.0",
              "lessThanOrEqual": "8.22.0",
              "versionType": "semver",
              "status": "affected"
            },
            {
              "version": "8.21.0",
              "lessThanOrEqual": "8.21.0",
              "versionType": "semver",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N",
          "baseScore": 7.5,
          "baseSeverity": "HIGH",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "NONE",
          "integrityImpact": "HIGH",
          "availabilityImpact": "NONE"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 3.6
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-10-30T11:50:55.486110Z",
          "id": "CVE-2026-86415",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-201"
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://curl.se/docs/CVE-2026-86415.html",
      "source": "2499f714-1537-4658-8207-48ae4bb9eae9"
    },
    {
      "url": "https://curl.se/docs/CVE-2026-86415.json",
      "source": "2499f714-1537-4658-8207-48ae4bb9eae9"
    },
    {
      "url": "https://hackerone.com/reports/3993870",
      "source": "2499f714-1537-4658-8207-48ae4bb9eae9"
    }
  ]
}