UBUNTU-CVE-2026-53433 (CVE-2026-53433)

Vulnerability from osv_ubuntu – Published: 2026-06-30 13:19 – Updated: 2026-07-03 20:00 – Source website
VLAI
Details

fzf is vulnerable to a Denial of Service (DoS) due to inefficient HTTP body processing in the --listen mode due to inefficient HTTP body processing using repeated string concatenation, resulting in quadratic time complexity (O(n²)). A crafted POST request with many small segments can trigger excessive CPU usage during request handling.This allows a single malicious request to monopolize the single‑threaded HTTP server, blocking all other clients and resulting in denial of service. This issue was fixed in version 0.73.1.

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

{
  "affected": [
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "fzf",
            "binary_version": "0.20.0-1ubuntu0.1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:20.04:LTS",
        "name": "fzf",
        "purl": "pkg:deb/ubuntu/fzf@0.20.0-1ubuntu0.1?arch=source\u0026distro=focal"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.18.0-2",
        "0.18.0-3",
        "0.19.0-1",
        "0.20.0-1",
        "0.20.0-1ubuntu0.1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "fzf",
            "binary_version": "0.29.0-1ubuntu0.1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:22.04:LTS",
        "name": "fzf",
        "purl": "pkg:deb/ubuntu/fzf@0.29.0-1ubuntu0.1?arch=source\u0026distro=jammy"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.24.3-1",
        "0.29.0-1",
        "0.29.0-1ubuntu0.1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "fzf",
            "binary_version": "0.44.1-1ubuntu0.3"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:24.04:LTS",
        "name": "fzf",
        "purl": "pkg:deb/ubuntu/fzf@0.44.1-1ubuntu0.3?arch=source\u0026distro=noble"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.42.0-1build1",
        "0.44.1-1",
        "0.44.1-1ubuntu0.1",
        "0.44.1-1ubuntu0.2",
        "0.44.1-1ubuntu0.3"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "fzf",
            "binary_version": "0.60.3-1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:25.10",
        "name": "fzf",
        "purl": "pkg:deb/ubuntu/fzf@0.60.3-1?arch=source\u0026distro=questing"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.60.3-1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "fzf",
            "binary_version": "0.67.0-1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:26.04:LTS",
        "name": "fzf",
        "purl": "pkg:deb/ubuntu/fzf@0.67.0-1?arch=source\u0026distro=resolute"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.60.3-1",
        "0.66.0-1",
        "0.67.0-1"
      ]
    }
  ],
  "aliases": [],
  "details": "fzf is vulnerable to a Denial of Service (DoS) due to inefficient HTTP body processing in the --listen mode due to inefficient HTTP body processing using repeated string concatenation, resulting in quadratic time complexity (O(n\u00b2)). A crafted POST request with many small segments can trigger excessive CPU usage during request handling.This allows a single malicious request to monopolize the single\u2011threaded HTTP server, blocking all other clients and resulting in denial of service. This issue was fixed in version 0.73.1.",
  "id": "UBUNTU-CVE-2026-53433",
  "modified": "2026-07-03T20:00:12Z",
  "published": "2026-06-30T13:19:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-53433"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-53433"
    },
    {
      "type": "REPORT",
      "url": "https://cert.pl/en/posts/2026/06/CVE-2026-53432"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/junegunn/fzf"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/junegunn/fzf/commit/7963a2c6586c0b9eaa89b8995de8f0e08cf8a4ce"
    }
  ],
  "related": [],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    },
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2026-53433"
  ]
}



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