CVE-2021-29509 is a denial-of-service vulnerability affecting Puma, a Ruby/Rack HTTP server, specifically versions prior to 4.3.8 and 5.3.1. It allows an attacker to starve new connections by saturating all server threads with greedy persistent keep-alive connections, leading to unserved requests. Rated 7.5 HIGH (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H), this vulnerability is easily exploitable over the network with low attack complexity, resulting in a high impact on availability. There is no evidence of active exploitation, public exploit code (Metasploit, Nuclei, ExploitDB), or significant community discussion or media coverage regarding this CVE.
| Vendor | Product | Version(s) | CPE |
|---|---|---|---|
< 4.3.8CPE matchmatch criteria | cpe:2.3:a:puma:puma:*:*:*:*:*:ruby:*:* | ||
>= 5.0.0, < 5.3.1CPE matchmatch criteria | cpe:2.3:a:puma:puma:*:*:*:*:*:ruby:*:* | ||
10.0CPE matchmatch criteria | cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:* |
CVSS version used by this source: 3.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
The average CVE in this peer group has 0.0 Twitter, 0.0 Reddit, 0.1 Bluesky, 0.1 Mastodon, and 0.4 GitHub mentions.
No media coverage found for this CVE.
The average CVE in this peer group has 0.1 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.