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FKIE_CVE-2021-39240

Vulnerability from fkie_nvd - Published: 2021-08-17 19:15 - Updated: 2026-06-17 04:03
Severity
7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Summary
An issue was discovered in HAProxy 2.2 before 2.2.16, 2.3 before 2.3.13, and 2.4 before 2.4.3. It does not ensure that the scheme and path portions of a URI have the expected characters. For example, the authority field (as observed on a target HTTP/2 server) might differ from what the routing rules were intended to achieve.
References
cve@mitre.orghttps://git.haproxy.org/?p=haproxy.git%3Ba=commit%3Bh=4b8852c70d8c4b7e225e24eb58258a15eb54c26e
cve@mitre.orghttps://git.haproxy.org/?p=haproxy.git%3Ba=commit%3Bh=a495e0d94876c9d39763db319f609351907a31e8
cve@mitre.orghttps://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/4ALECUZDIMT5FYGP6V6PVSI4BKVZTZWN/
cve@mitre.orghttps://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/RPNY4WZIQUAUOCLIMUPC37AQWNXTWIQM/
cve@mitre.orghttps://www.debian.org/security/2021/dsa-4960Third Party Advisory
cve@mitre.orghttps://www.mail-archive.com/haproxy%40formilux.org/msg41041.html
af854a3a-2127-422b-91ae-364da2661108https://git.haproxy.org/?p=haproxy.git%3Ba=commit%3Bh=4b8852c70d8c4b7e225e24eb58258a15eb54c26e
af854a3a-2127-422b-91ae-364da2661108https://git.haproxy.org/?p=haproxy.git%3Ba=commit%3Bh=a495e0d94876c9d39763db319f609351907a31e8
af854a3a-2127-422b-91ae-364da2661108https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/4ALECUZDIMT5FYGP6V6PVSI4BKVZTZWN/
af854a3a-2127-422b-91ae-364da2661108https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/RPNY4WZIQUAUOCLIMUPC37AQWNXTWIQM/
af854a3a-2127-422b-91ae-364da2661108https://www.debian.org/security/2021/dsa-4960Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://www.mail-archive.com/haproxy%40formilux.org/msg41041.html
Impacted products
Vendor Product Version
haproxy haproxy *
haproxy haproxy *
haproxy haproxy *
debian debian_linux 11.0
fedoraproject fedora 33
fedoraproject fedora 34
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "n/a",
          "vendor": "n/a",
          "versions": [
            {
              "status": "affected",
              "version": "n/a"
            }
          ]
        }
      ],
      "source": "cve@mitre.org"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:haproxy:haproxy:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "B8A35038-8767-48F3-B81F-81FCD0B31D32",
              "versionEndExcluding": "2.2.16",
              "versionStartIncluding": "2.2.0",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:a:haproxy:haproxy:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "040439D6-C0FC-4550-884E-1B3FB396A5DF",
              "versionEndExcluding": "2.3.13",
              "versionStartIncluding": "2.3.0",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:a:haproxy:haproxy:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "88FF602C-41E1-4569-B09B-161BB7C85891",
              "versionEndExcluding": "2.4.3",
              "versionStartIncluding": "2.4.0",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    },
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*",
              "matchCriteriaId": "FA6FEEC2-9F11-4643-8827-749718254FED",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    },
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*",
              "matchCriteriaId": "E460AA51-FCDA-46B9-AE97-E6676AA5E194",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*",
              "matchCriteriaId": "A930E247-0B43-43CB-98FF-6CE7B8189835",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "An issue was discovered in HAProxy 2.2 before 2.2.16, 2.3 before 2.3.13, and 2.4 before 2.4.3. It does not ensure that the scheme and path portions of a URI have the expected characters. For example, the authority field (as observed on a target HTTP/2 server) might differ from what the routing rules were intended to achieve."
    },
    {
      "lang": "es",
      "value": "Se ha detectado un problema en HAProxy versiones 2.2 anteriores a 2.2.16, versiones 2.3 anteriores a 2.3.13 y versiones 2.4 anteriores a 2.4.3. No se asegura que las porciones de esquema y ruta de un URI tengan los caracteres esperados. Por ejemplo, el campo authority (como es observado en un servidor HTTP/2 de destino) podr\u00eda diferir de lo que las reglas de enrutamiento pretend\u00edan lograr."
    }
  ],
  "id": "CVE-2021-39240",
  "lastModified": "2026-06-17T04:03:22.870",
  "metrics": {
    "cvssMetricV2": [
      {
        "acInsufInfo": false,
        "baseSeverity": "MEDIUM",
        "cvssData": {
          "accessComplexity": "LOW",
          "accessVector": "NETWORK",
          "authentication": "NONE",
          "availabilityImpact": "NONE",
          "baseScore": 5.0,
          "confidentialityImpact": "PARTIAL",
          "integrityImpact": "NONE",
          "vectorString": "AV:N/AC:L/Au:N/C:P/I:N/A:N",
          "version": "2.0"
        },
        "exploitabilityScore": 10.0,
        "impactScore": 2.9,
        "obtainAllPrivilege": false,
        "obtainOtherPrivilege": false,
        "obtainUserPrivilege": false,
        "source": "nvd@nist.gov",
        "type": "Primary",
        "userInteractionRequired": false
      }
    ],
    "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": "nvd@nist.gov",
        "type": "Primary"
      }
    ]
  },
  "published": "2021-08-17T19:15:08.247",
  "references": [
    {
      "source": "cve@mitre.org",
      "url": "https://git.haproxy.org/?p=haproxy.git%3Ba=commit%3Bh=4b8852c70d8c4b7e225e24eb58258a15eb54c26e"
    },
    {
      "source": "cve@mitre.org",
      "url": "https://git.haproxy.org/?p=haproxy.git%3Ba=commit%3Bh=a495e0d94876c9d39763db319f609351907a31e8"
    },
    {
      "source": "cve@mitre.org",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/4ALECUZDIMT5FYGP6V6PVSI4BKVZTZWN/"
    },
    {
      "source": "cve@mitre.org",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/RPNY4WZIQUAUOCLIMUPC37AQWNXTWIQM/"
    },
    {
      "source": "cve@mitre.org",
      "tags": [
        "Third Party Advisory"
      ],
      "url": "https://www.debian.org/security/2021/dsa-4960"
    },
    {
      "source": "cve@mitre.org",
      "url": "https://www.mail-archive.com/haproxy%40formilux.org/msg41041.html"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "url": "https://git.haproxy.org/?p=haproxy.git%3Ba=commit%3Bh=4b8852c70d8c4b7e225e24eb58258a15eb54c26e"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "url": "https://git.haproxy.org/?p=haproxy.git%3Ba=commit%3Bh=a495e0d94876c9d39763db319f609351907a31e8"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/4ALECUZDIMT5FYGP6V6PVSI4BKVZTZWN/"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/RPNY4WZIQUAUOCLIMUPC37AQWNXTWIQM/"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Third Party Advisory"
      ],
      "url": "https://www.debian.org/security/2021/dsa-4960"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "url": "https://www.mail-archive.com/haproxy%40formilux.org/msg41041.html"
    }
  ],
  "sourceIdentifier": "cve@mitre.org",
  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "NVD-CWE-noinfo"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    }
  ]
}



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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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.


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