There is a denial of service vulnerability in the header parsing component of Rack.
https://github.com/advisories/GHSA-c6qg-cjj8-47qp
https://www.debian.org/security/2023/dsa-5530
https://security.netapp.com/advisory/ntap-20231208-0016/
https://lists.debian.org/debian-lts-announce/2023/04/msg00017.html
https://github.com/rack/rack/commit/ee7919ea04303717858be1c3f16b406adc6d8cff
https://github.com/rack/rack/commit/231ef369ad0b542575fb36c74fcfcfabcf6c530c