CVE-2025-6442

Publication date 25 June 2025

Last updated 1 August 2025

Ubuntu priority

Medium

Why this priority?

Cvss 3 Severity Score

6.5 · Medium

Score breakdown

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.

Status

Package Ubuntu Release Status
ruby-webrick 25.04 plucky
Vulnerable
24.10 oracular Ignored end of life, was needs-triage
24.04 LTS noble
Vulnerable
22.04 LTS jammy
Vulnerable

Patch details

For informational purposes only. We recommend not to cherry-pick updates. How can I get the fixes?

Package Patch details
ruby-webrick

Severity score breakdown

Parameter Value
Base score 6.5 · Medium
Attack vector Network
Attack complexity High
Privileges required None
User interaction None
Scope Unchanged
Confidentiality Low
Integrity impact High
Availability impact None
Vector CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:H/A:N

References

Related Ubuntu Security Notices (USN)

Other references