CVE-2025-49007: ReDoS Vulnerability in Rack::Multipart handle_mime_head
Summary There is a denial of service vulnerability in the Content-Disposition parsing component of Rack. This is very similar to the previous security issue CVE-2022-44571.
Details
Carefully crafted input can cause Content-Disposition header parsing in Rack to take an unexpected amount of time, possibly resulting in a denial of service attack vector. This header is used typically used in multipart parsing. Any applications that parse multipart posts using Rack (virtually all Rails applications) are impacted.
Credits
Thanks to scyoon for reporting this to the Rails security team
Other sources
Rack is a modular Ruby web server interface. Starting in version 3.1.0 and prior to version 3.1.16, there is a denial of service vulnerability in the Content-Disposition parsing component of Rack. This is very similar to the previous security issue CVE-2022-44571. Carefully crafted input can cause Content-Disposition header parsing in Rack to take an unexpected amount of time, possibly resulting in a denial of service attack vector. This header is used typically used in multipart parsing. Any applications that parse multipart posts using Rack (virtually all Rails applications) are impacted. Version 3.1.16 contains a patch for the vulnerability.
— MITRE
Affected Software
Remediation
Event History
Frequently Asked Questions
What is the severity of CVE-2025-49007?
CVE-2025-49007 is identified as a denial of service vulnerability.
How do I fix CVE-2025-49007?
To mitigate CVE-2025-49007, upgrade Rack to version 3.1.16 or later.
Which versions of Rack are affected by CVE-2025-49007?
CVE-2025-49007 affects Rack versions from 3.1.0 to 3.1.15.
Is CVE-2025-49007 related to any previous vulnerabilities?
Yes, CVE-2025-49007 is similar to the previous vulnerability CVE-2022-44571.
What component of Rack does CVE-2025-49007 impact?
CVE-2025-49007 impacts the Content-Disposition parsing component of Rack.