Ruby WEBrick read_header HTTP Request Smuggling Vulnerability (Ruby WEBrick)

CVE-2025-6442
MEDIUM 6.5

At a glance

Source
NVD
EPSS
EPSS 0.50 % · percentile 42 ()
State
PUBLISHED
Published
Updated
Assigner
zdi
NVD status
Analyzed

Description

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.

Weaknesses (CWE)

  • CWE-444 — Inconsistent Interpretation of HTTP Requests

References

Scores

VersionScoreVectorScored by
CVSS 3.0MEDIUM 6.5CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:H/A:Nzdi
CVSS 3.1MEDIUM 5.9CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:NNVD · nvd@nist.gov (Primary)
CVSS 3.0MEDIUM 6.5CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:H/A:NNVD · zdi-disclosures@trendmicro.com (Secondary)

Advisories

European references

CERT-FR advisories

Affected configurations (NVD CPE)

Affected products

ProductVersions
Ruby · WEBrickaffected 1.8.1

Sources

SourceLicence
CVE List (CVEProject cvelistV5)CVE Program Terms of Use
EPSS (FIRST.org)FIRST — attribution requested
ENISA EUVDENISA — reproduction authorised, source acknowledged
CERT-FR (ANSSI)Licence Ouverte / Etalab 2.0
NVD (NIST) via fkie-cad/nvd-json-data-feedsPublic domain — this product uses data from the NVD API but is not endorsed or certified by the NVD