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ubuntu-cve-2026-21428
Vulnerability from osv_ubuntu
Published
2026-01-01 18:15
Modified
2026-06-25 11:14
Summary
Details

cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to version 0.30.0, the write_headers function does not check for CR & LF characters in user supplied headers, allowing untrusted header value to escape header lines. This vulnerability allows attackers to add extra headers, modify request body unexpectedly & trigger an SSRF attack. When combined with a server that supports http1.1 pipelining (springboot, python twisted etc), this can be used for server side request forgery (SSRF). Version 0.30.0 fixes this issue.

Severity
7.7 (High)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:P
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
N/A (UNKNOWN)
medium
References
To clipboard 

{
  "affected": [
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "libcpp-httplib0",
            "binary_version": "0.10.3+ds-1ubuntu0.1~esm2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:22.04:LTS",
        "name": "cpp-httplib",
        "purl": "pkg:deb/ubuntu/cpp-httplib@0.10.3+ds-1ubuntu0.1~esm2?arch=source\u0026distro=esm-apps/jammy"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.9.9+ds-1",
        "0.9.10+ds-1",
        "0.10.1+ds-1",
        "0.10.2+ds-1",
        "0.10.3+ds-1",
        "0.10.3+ds-1ubuntu0.1~esm1",
        "0.10.3+ds-1ubuntu0.1~esm2"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "libcpp-httplib0.14t64",
            "binary_version": "0.14.3+ds-1.1ubuntu0.1~esm2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:24.04:LTS",
        "name": "cpp-httplib",
        "purl": "pkg:deb/ubuntu/cpp-httplib@0.14.3+ds-1.1ubuntu0.1~esm2?arch=source\u0026distro=esm-apps/noble"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.13.1+ds-1ubuntu1",
        "0.14.3+ds-1",
        "0.14.3+ds-1.1",
        "0.14.3+ds-1.1build1",
        "0.14.3+ds-1.1build2",
        "0.14.3+ds-1.1ubuntu0.1~esm1",
        "0.14.3+ds-1.1ubuntu0.1~esm2"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "libcpp-httplib0.18",
            "binary_version": "0.18.7-1ubuntu0.25.10.2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:25.10",
        "name": "cpp-httplib",
        "purl": "pkg:deb/ubuntu/cpp-httplib@0.18.7-1ubuntu0.25.10.2?arch=source\u0026distro=questing"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.18.7-1",
        "0.18.7-1ubuntu0.25.10.1",
        "0.18.7-1ubuntu0.25.10.2"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "libcpp-httplib0.26",
            "binary_version": "0.26.0+ds-2ubuntu3+esm1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:26.04:LTS",
        "name": "cpp-httplib",
        "purl": "pkg:deb/ubuntu/cpp-httplib@0.26.0+ds-2ubuntu3+esm1?arch=source\u0026distro=esm-apps/resolute"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.18.7-1",
        "0.26.0+ds-2ubuntu2",
        "0.26.0+ds-2ubuntu3",
        "0.26.0+ds-2ubuntu3+esm1"
      ]
    }
  ],
  "aliases": [],
  "details": "cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to version 0.30.0, the ``write_headers`` function does not check for CR \u0026 LF characters in user supplied headers, allowing untrusted header value to escape header lines. This vulnerability allows attackers to add extra headers, modify request body unexpectedly \u0026 trigger an SSRF attack. When combined with a server that supports http1.1 pipelining (springboot, python twisted etc), this can be used for server side request forgery (SSRF). Version 0.30.0 fixes this issue.",
  "id": "UBUNTU-CVE-2026-21428",
  "modified": "2026-06-25T11:14:15Z",
  "published": "2026-01-01T18:15:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-21428"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-21428"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/yhirose/cpp-httplib/security/advisories/GHSA-wpc6-j37r-jcx7"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/yhirose/cpp-httplib/commit/98048a033a532ff22320ce1d11789f8d5710dfcd"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/yhirose/cpp-httplib/releases/tag/v0.30.0"
    }
  ],
  "related": [],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:P",
      "type": "CVSS_V4"
    },
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2026-21428"
  ]
}



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