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
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
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
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
Impacted products
Vendor Product Version CPE status
fzf fzf Affected: 0 , < 0.73.1 (semver)
guessed Create a notification for this product.
Date Public
2026-06-30 12:01
Credits
Michał Majchrowicz (AFINE Team) Marcin Wyczechowski (AFINE Team)
Show details on NVD website
To clipboard 

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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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