cbcvebase.
CVE-2025-6442
published 2025-06-25

CVE-2025-6442: Ruby WEBrick read_header HTTP Request Smuggling Vulnerability. This vulnerability allows remote attackers to smuggle arbitrary HTTP requests on affected…

PriorityP335medium5.9CVSS 3.1
AVNACHPRNUINSUCNIHAN
EPSS
0.42%
33.8th percentile
Ruby WEBrick read_header HTTP Request Smuggling Vulnerability. This vulnerability allows remote attackers to smuggle arbitrary HTTP requests on affected installations of Ruby WEBrick. This issue is exploitable when the product is deployed behind an HTTP proxy that fulfills specific conditions. The specific flaw exists within the read_headers method. The issue results from the inconsistent parsing of terminators of HTTP headers. An attacker can leverage this vulnerability to smuggle arbitrary HTTP requests. Was ZDI-CAN-21876.

Affected

7 ranges
VendorProductVersion rangeFixed in
applemacos_sequoia
applemacos_sonoma
applemacos_tahoe
debianruby-webrick< ruby-webrick 1.9.1-1 (forky)ruby-webrick 1.9.1-1 (forky)
ruby-langwebrick< 1.8.21.8.2
ruby-langwebrick>= 0 < 1.8.21.8.2
rubywebrick

CVSS provenance

nvdv3.15.9MEDIUMCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N
nvdv3.06.5MEDIUMCVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:H/A:N
osv5.9MEDIUM
vendor_debian5.9MEDIUM
vendor_redhat5.9MEDIUM
vendor_ubuntu5.3MEDIUM
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