cvedb.io
CVE-2026-34830
MEDIUM · CVSS 5.9
EPSS exploitation probability: 0%
Published 2026-04-02T17:16:26.267 · Last modified 2026-06-17T10:39:42.463

Summary

Rack is a modular Ruby web server interface. Prior to versions 2.2.23, 3.1.21, and 3.2.6, Rack::Sendfile#map_accel_path interpolates the value of the X-Accel-Mapping request header directly into a regular expression when rewriting file paths for X-Accel-Redirect. Because the header value is not escaped, an attacker who can supply X-Accel-Mapping to the backend can inject regex metacharacters and control the generated X-Accel-Redirect response header. In deployments using Rack::Sendfile with x-accel-redirect, this can allow an attacker to cause nginx to serve unintended files from configured internal locations. This issue has been patched in versions 2.2.23, 3.1.21, and 3.2.6.

Affected products

rack — rack

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References

This product uses data from the NVD API but is not endorsed or certified by the NVD. Informational only; not professional security advice.