CVE-2026-53433

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{"bugzilla": {"description": "fzf: fzf: Denial of Service via inefficient HTTP body processing", "id": "2494891", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2494891"}, "csaw": false, "cvss3": {"cvss3_base_score": "7.5", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "status": "draft"}, "cwe": "CWE-1046", "details": ["A flaw was found in fzf, a command-line fuzzy finder. This vulnerability allows a remote attacker to cause a Denial of Service (DoS) by sending a crafted POST request with many small segments to the `--listen` mode. The inefficient HTTP body processing, which uses repeated string concatenation, leads to quadratic time complexity, causing excessive CPU usage and blocking other clients."], "mitigation": {"lang": "en:us", "value": "Do not use fzf's --listen mode in untrusted network environments. If --listen is required, restrict network access to the fzf listener port using firewall rules."}, "name": "CVE-2026-53433", "public_date": "2026-06-30T12:01:14Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-53433\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-53433\nhttps://cert.pl/en/posts/2026/06/CVE-2026-53432\nhttps://github.com/junegunn/fzf\nhttps://github.com/junegunn/fzf/commit/7963a2c6586c0b9eaa89b8995de8f0e08cf8a4ce"], "statement": "A flaw was found in fzf, a command-line fuzzy finder. When fzf is running in --listen mode (a non-default, opt-in feature), inefficient HTTP body processing using repeated string concatenation results in quadratic time complexity. A crafted POST request can monopolize the single-threaded HTTP server, causing denial of service. Red Hat has corrected the impact from IMPORTANT to MODERATE \u2014 the original AI-Bot CVSS of 7.5 (AV:N/AC:L) did not account for the --listen mode being a non-default feature that must be explicitly enabled. The CVEORG CVSSv4 score of 5.7 (AV:L/AT:P) more accurately reflects the prerequisite nature of the attack.", "threat_severity": "Moderate"}

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