GitHub Advisoryadvisory · Go

GHSA-mvmf-94v6-879g fzf vulnerable to denial of service through quadratic HTTP request-body accumulation

MEDIUM Published 2026-06-30 Modified 2026-09-30 Official page ↗
Aliases
CVE-2026-53433
Ecosystem
Go
Packages
github.com/junegunn/fzf
Severity
Moderate
CVSS vector
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
Weaknesses
CWE-407
Reviewed
2026-09-30

Affected packages

• Go github.com/junegunn/fzf: < 0.73.1 → fixed in 0.73.1

Description

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.

Related

Alias · CVE (1)

  • CVE-2026-53433 fzf is vulnerable to a Denial of Service (DoS) due to inefficient HTTP body processing in the --listen mode due to inefficient HTTP body… vulnerability

Weakness · CWE (1)

  • CWE-407 Inefficient Algorithmic Complexity weakness

References