CVE-2026-34230

medium Red Hat
CVSS v3 Base Score
5.3
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
EPSS Score
0.0%
Exploitation probability in 30 days
Top 93% most likely to be exploited
Attack Characteristics
Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Confidentiality
None
Integrity
None
Availability
Low
Published: April 2, 2026 (99 days ago)
Last Modified: April 2, 2026
Vendor: Red Hat
Source: REDHAT

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.

CWE

CWE-1050

Affected Products

Logging Subsystem for Red Hat OpenShiftRed Hat 3scale API Management Platform 2Red Hat Enterprise Linux 10Red Hat Enterprise Linux 7Red Hat Enterprise Linux 8Red Hat Enterprise Linux 9

References

🔗 bugzilla.redhat.com 🔗 www.cve.org 🔗 nvd.nist.gov 🔗 github.com