Is CVE-2026-34230 actively exploited?

No active exploitation of CVE-2026-34230 has been confirmed so far. Continue monitoring, as exploit status can change.

Can CVE-2026-34230 be exploited remotely?

Yes. CVE-2026-34230 is exploitable remotely over the network (CVSS attack vector: Network).

What is the CVSS score of CVE-2026-34230?

CVE-2026-34230 has a CVSS score of 5.3 (MEDIUM).

HOME VULNERABILITIESCVE-2026-34230

MEDIUM

CVE-2026-34230

CWE-400Published: April 2, 2026· Updated: Apr 3, 2026

5.3

CVSS v3.1

EPSS:0.04%probability of exploitation in 30 daysPercentile:11.9th

Official Description

Rack is a modular Ruby web server interface. Prior to versions 2.2.23, 3.1.21, and 3.2.6, Rack::Utils.select_best_encoding processes Accept-Encoding values with quadratic time complexity when the header contains many wildcard (*) entries. Because this method is used by Rack::Deflater to choose a response encoding, an unauthenticated attacker can send a single request with a crafted Accept-Encoding header and cause disproportionate CPU consumption on the compression middleware path. This results in a denial of service condition for applications using Rack::Deflater. This issue has been patched in versions 2.2.23, 3.1.21, and 3.2.6.

NVD Source

Technical Analysis

CVE-2026-34230 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.

The vulnerability requires no privileges and no user interaction, making it a prime target for automated exploitation campaigns and worm-like propagation.