6.5

CVE-2026-34835

Exploit

Rack: `Rack::Request` accepts invalid Host characters, enabling host allowlist bypass.

Rack is a modular Ruby web server interface. From versions 3.0.0.beta1 to before 3.1.21, and 3.2.0 to before 3.2.6, Rack::Request parses the Host header using an AUTHORITY regular expression that accepts characters not permitted in RFC-compliant hostnames, including /, ?, #, and @. Because req.host returns the full parsed value, applications that validate hosts using naive prefix or suffix checks can be bypassed. This can lead to host header poisoning in applications that use req.host, req.url, or req.base_url for link generation, redirects, or origin validation. This issue has been patched in versions 3.1.21 and 3.2.6.
Daten sind bereitgestellt durch National Vulnerability Database (NVD)
Rack ≫ Rack SwPlatformruby Version >= 3.0.0 < 3.1.21
Rack ≫ Rack SwPlatformruby Version >= 3.2.0 < 3.2.6
VulnDex Vulnerability Enrichment
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Zu dieser CVE wurde keine Warnung gefunden.
EPSS Metriken
Typ Quelle Score Percentile
EPSS FIRST.org 0.15% 0.355
CVSS Metriken
Quelle Base Score Exploit Score Impact Score Vector String
nvd@nist.gov 6.5 3.9 2.5
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
security-advisories@github.com 4.8 2.2 2.5
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N
CWE-1286 Improper Validation of Syntactic Correctness of Input

The product receives input that is expected to be well-formed - i.e., to comply with a certain syntax - but it does not validate or incorrectly validates that the input complies with the syntax.