CVE-2026-53433 (GCVE-0-2026-53433)
Vulnerability from cvelistv5 – Published: 2026-06-30 12:01 – Updated: 2026-06-30 13:32 X_Open Source
VLAI
EPSS
VEX
Title
Denial of Service in fzf
Summary
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
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-06-30 13:32 UTC
CWE
- CWE-407 - Inefficient Algorithmic Complexity
Assigner
References
3 references
| URL | Tags |
|---|---|
| https://cert.pl/en/posts/2026/06/CVE-2026-53432 | third-party-advisory |
| https://github.com/junegunn/fzf | product |
| https://github.com/junegunn/fzf/commit/7963a2c658… | issue-tracking |
Impacted products
Date Public
2026-06-30 12:01
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
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The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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Related by attack behaviour
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