What is CVE-2026-34829?

CVE-2026-34829 is a high-severity vulnerability in Rack, classified under Uncontrolled Resource Consumption. CVSS score: 7.5/10. Published 2026-04-02.

How severe is CVE-2026-34829?

High severity. CVSS v3 base score is 7.5 out of 10.

Resource exhaustion in Rack

CVE-2026-34829

Rack is a modular Ruby web server interface. Prior to versions 2.2.23, 3.1.21, and 3.2.6, Rack::Multipart::Parser only wraps the request body in a BoundedIO when CONTENT_LENGTH is present. When a multipart/form-data request is sent without…

Vulnerability class: DoS (Denial of Service)

EPSS: 0.001 (20.4th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

Affected products

Rack — versions < 2.2.23, >= 3.0.0.beta1, < 3.1.21, >= 3.2.0, < 3.2.6

Weakness classification (CWE)

References

https://github.com/rack/rack/security/advisories/GHSA-8vqr-qjwx-82mw (x_refsource_CONFIRM)

Frequently asked questions

What is CVE-2026-34829?: CVE-2026-34829 is a high-severity vulnerability in Rack, classified under Uncontrolled Resource Consumption. CVSS score: 7.5/10. Published 2026-04-02.
How severe is CVE-2026-34829?: High severity. CVSS v3 base score is 7.5 out of 10.