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FKIE_CVE-2026-80255

Vulnerability from fkie_nvd - Published: 2026-09-06 18:17 - Updated: 2026-09-11 20:02
Severity
7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Summary
A `Set-Cookie:` header using tab (horizontal tab, ASCII code 9) instead of space (ascii code 32) immediately before the `Secure` attribute causes curl to store the cookie without its Secure flag. The cookie might then wrongfully be sent over plaintext HTTP on subsequent requests to the same host.
References
2499f714-1537-4658-8207-48ae4bb9eae9https://curl.se/docs/CVE-2026-80255.htmlPatch, Vendor Advisory
2499f714-1537-4658-8207-48ae4bb9eae9https://curl.se/docs/CVE-2026-80255.jsonVendor Advisory
2499f714-1537-4658-8207-48ae4bb9eae9https://hackerone.com/reports/3972395Exploit, Mitigation, Third Party Advisory
134c704f-9b21-4f2e-91b3-4a467353bcc0https://hackerone.com/reports/3972395Exploit, Mitigation, Third Party Advisory
Impacted products
Vendor Product Version
haxx curl *
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "curl",
          "vendor": "curl",
          "versions": [
            {
              "lessThanOrEqual": "8.21.0",
              "status": "affected",
              "version": "8.21.0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "8.20.0",
              "status": "affected",
              "version": "8.20.0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "8.19.0",
              "status": "affected",
              "version": "8.19.0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "8.18.0",
              "status": "affected",
              "version": "8.18.0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "8.17.0",
              "status": "affected",
              "version": "8.17.0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "8.16.0",
              "status": "affected",
              "version": "8.16.0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "8.15.0",
              "status": "affected",
              "version": "8.15.0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "8.14.1",
              "status": "affected",
              "version": "8.14.1",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "8.14.0",
              "status": "affected",
              "version": "8.14.0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "8.13.0",
              "status": "affected",
              "version": "8.13.0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "source": "2499f714-1537-4658-8207-48ae4bb9eae9"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:haxx:curl:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "99A8196C-041E-486F-80D8-40CFD4810C11",
              "versionEndExcluding": "8.22.0",
              "versionStartIncluding": "8.13.0",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "A `Set-Cookie:` header using tab (horizontal tab, ASCII code 9) instead of\nspace (ascii code 32) immediately before the `Secure` attribute causes curl to\nstore the cookie without its Secure flag. The cookie might then wrongfully be\nsent over plaintext HTTP on subsequent requests to the same host."
    }
  ],
  "id": "CVE-2026-80255",
  "lastModified": "2026-09-11T20:02:30.160",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 7.5,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "NONE",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
          "version": "3.1"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 3.6,
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-80255",
          "options": [
            {
              "exploitation": "poc"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-09-08T18:45:09.883106Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-09-06T18:17:22.623",
  "references": [
    {
      "source": "2499f714-1537-4658-8207-48ae4bb9eae9",
      "tags": [
        "Patch",
        "Vendor Advisory"
      ],
      "url": "https://curl.se/docs/CVE-2026-80255.html"
    },
    {
      "source": "2499f714-1537-4658-8207-48ae4bb9eae9",
      "tags": [
        "Vendor Advisory"
      ],
      "url": "https://curl.se/docs/CVE-2026-80255.json"
    },
    {
      "source": "2499f714-1537-4658-8207-48ae4bb9eae9",
      "tags": [
        "Exploit",
        "Mitigation",
        "Third Party Advisory"
      ],
      "url": "https://hackerone.com/reports/3972395"
    },
    {
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "tags": [
        "Exploit",
        "Mitigation",
        "Third Party Advisory"
      ],
      "url": "https://hackerone.com/reports/3972395"
    }
  ],
  "sourceIdentifier": "2499f714-1537-4658-8207-48ae4bb9eae9",
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-201"
        }
      ],
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "type": "Secondary"
    }
  ]
}



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Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.