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CVE-2026-125108

3.7 lowEPSS 0.2%

Low (3.7) in rack rack. EPSS 0.2% estimated probability of exploitation activity in the next 30 days.

On this page
Rack is a modular Ruby web server interface. Prior to 2.2.25, 3.1.23, and 3.2.8, Rack::Multipart::Parser.parse_boundary can skip a leading empty or quoted boundary parameter in a multipart Content-Type header and accept a later parameter. Rack can therefore parse a request body with a boundary that a conforming intermediary would not derive, allowing form fields or file uploads to reach an application without the intended proxy or web application firewall inspection. This issue is fixed in versions 2.2.25, 3.1.23, and 3.2.8.

Severity

CVSS 3.1

3.7 low
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N
EPSS
0.2% estimated probability of exploitation activity in the next 30 days; 15th percentile. Scored 2026-11-10. A forecast for this CVE across the internet, not for your own systems.
CWE
CWE-436 Interpretation Conflict
OWASP Top 10
A06:2025 Insecure Design
Published
Assigned by
GitHub_M (CNA)
NVD analysis
Not in the NVD yet
Record from
the CVE List, synced

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Affected

Versions

From the CNA's record in the CVE List.

ProductAffected
rack< 2.2.25
rack>= 3.0, < 3.1.23
rack>= 3.2, < 3.2.8

Linux distributions

DistributionReleasePackageFixed inAdvisory
Debian12, 13ruby-rackno fix listedDEBIAN-CVE-2026-125108
Debian14ruby-rack3.2.8-1DEBIAN-CVE-2026-125108

From the distributions' data via OSV.dev: the Debian Security Tracker. Modified: reformatted and linked to CVE records. Credits. On the distributions' own pages: Debian.

Attack patterns (CAPEC)

  • CAPEC-34 HTTP Response Splitting Likelihood: Medium · Severity: High
  • CAPEC-105 HTTP Request Splitting Likelihood: Medium · Severity: High
  • CAPEC-273 HTTP Response Smuggling Likelihood: Medium · Severity: High

The attack patterns MITRE's CAPEC relates to this record's weaknesses, as MITRE names them. Credits.

References

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