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

Q: How do I fix CVE-2026-53433?

fzf: upgrade to 0.73.1. Exact commands for each OS are on this page.

Q: Is CVE-2026-53433 being exploited?

CVE-2026-53433 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

Q: What does CVE-2026-53433 affect?

CVE-2026-53433 affects fzf. Severity is high (CVSS 7.5). 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 craft

Q: How urgent is CVE-2026-53433?

Priority 39/100. High severity; Remotely exploitable, no login, no user action

Routine

HIGH 7.5REMOTEUPGRADE

CVE-2026-53433 is a high-severity flaw (CVSS 7.5) affecting fzf. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

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

Why this priority

High severity
Remotely exploitable, no login, no user action

A fixed release or distro patch exists.

Risk facts

CVSS score	7.5 (High)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	None
EPSS exploit chance	0.4% (top 68%)
CISA exploited list	No
Weakness	CWE-407
Published	2026-06-30
Last modified	2026-07-02

Publisher (CNA): CERT.PL · Vendor: junegunn

Last updated 2026-07-02 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2026-06-30 13:19 UTCPublished CVE record published
2026-07-02 19:01 UTCUpdated Record last modified

junegunn fzf UPGRADE

Affected: < 0.73.1

Fixed in: 0.73.1

Safe to downgrade to: no unaffected older release

1. Check installed version

apt-cache policy fzf || rpm -q fzf || fzf --version

2. UPGRADE to 0.73.1 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade fzf

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade fzf

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

Advisories and coverage

Official advisories

CERT Polska: Vulnerabilities in fzf software 2026-06-30

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2026-53433?

fzf: upgrade to 0.73.1. Exact commands for each OS are on this page.

Is CVE-2026-53433 being exploited?

CVE-2026-53433 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2026-53433 affect?

CVE-2026-53433 affects fzf. Severity is high (CVSS 7.5). 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 craft

How urgent is CVE-2026-53433?

Priority 39/100. High severity; Remotely exploitable, no login, no user action

Related CVEs

CVE-2026-53432 HIGH 7.5 UPGRADE fzf is vulnerable to Integer Overflow leading to crash in FuzzyMatchV2 function

References

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