Possible Denial of Service Vulnerability in Rack’s header parsing
Published: March 13, 2023
SECURITY IDENTIFIERS
- CVE: CVE-2023-27539 (NVD)
- GHSA: GHSA-c6qg-cjj8-47qp
- Vendor Advisory: https://discuss.rubyonrails.org/t/cve-2023-27539-possible-denial-of-service-vulnerability-in-racks-header-parsing/82466
GEM
PATCHED VERSIONS
~> 2.0, >= 2.2.6.4
>= 3.0.6.1
DESCRIPTION
There is a denial of service vulnerability in the header parsing component of Rack. This vulnerability has been assigned the CVE identifier CVE-2023-27539.
Versions Affected: >= 2.0.0 Not affected: None. Fixed Versions: 2.2.6.4, 3.0.6.1
Impact
Carefully crafted input can cause header parsing in Rack to take an unexpected amount of time, possibly resulting in a denial of service attack vector. Any applications that parse headers using Rack (virtually all Rails applications) are impacted.
Workarounds
Setting Regexp.timeout in Ruby 3.2 is a possible workaround.