Vulnerability · Published Oct 22, 2026 · Assigned by VulnCheck
CVE-2026-115319fzf 0.36.0 through 0.74.5 Denial of Service via maskActionContents
Low 2.5
In plain English
A low-severity security flaw in fzf from junegunn. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.1% (higher than 1% of all known vulnerabilities).
Severity (CVSS 3.1)2.5Low
Exploit odds (30 days)0.1%top 99.1% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official description
fzf 0.36.0 through 0.74.5 contains an inefficient algorithmic complexity vulnerability in maskActionContents that allows local attackers to exhaust the --listen HTTP server through quadratic string concatenation. Attackers can repeatedly send POST bodies of about 1 MB to the unauthenticated localhost port, blocking the single-threaded server for about 30 seconds each time.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | fzf | no fix listed | DEBIAN-CVE-2026-115319 |
| Debian:13 | fzf | no fix listed | DEBIAN-CVE-2026-115319 |
| Debian:14 | fzf | no fix listed | DEBIAN-CVE-2026-115319 |
| Ubuntu:22.04:LTS | fzf | no fix listed | UBUNTU-CVE-2026-115319 |
| Ubuntu:24.04:LTS | fzf | no fix listed | UBUNTU-CVE-2026-115319 |
| Ubuntu:26.04:LTS | fzf | no fix listed | UBUNTU-CVE-2026-115319 |
| Ubuntu:26.10 | fzf | no fix listed | UBUNTU-CVE-2026-115319 |
Affected products (as reported)
Weakness: CWE-407 · Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L
References
- Patch Commit patch
- https://github.com/junegunn/fzf/blob/v0.74.5/src/options.go#L1680-L1736 technical-description
- https://github.com/junegunn/fzf product
- VulnCheck Advisory: fzf 0.36.0 through 0.74.5 Denial of Service via maskActionContents third-party-advisory