{"id":"CVE-2021-39185","aliases":["GHSA-52cf-226f-rhr6"],"url":"https://o3.security/vulnerability/CVE-2021-39185","summary":"Default CORS config allows any origin with credentials","details":"Http4s is a minimal, idiomatic Scala interface for HTTP services. In http4s versions 0.21.26 and prior, 0.22.0 through 0.22.2, 0.23.0, 0.23.1, and 1.0.0-M1 through 1.0.0-M24, the default CORS configuration is vulnerable to an origin reflection attack. The middleware is also susceptible to a Null Origin Attack. The problem is fixed in 0.21.27, 0.22.3, 0.23.2, and 1.0.0-M25. The original `CORS` implementation and `CORSConfig` are deprecated. See the GitHub GHSA for more information, including code examples and workarounds.","published":"2021-09-01T20:15:07.447Z","modified":"2026-07-09T10:52:20.589461Z","cvss":{"score":9.1,"severity":"CRITICAL","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N"},"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Maven","name":"org.http4s:http4s-server_2.13.0-M5","fixedVersion":null},{"ecosystem":"Maven","name":"org.http4s:http4s-server_3","fixedVersion":"0.22.3"},{"ecosystem":"Maven","name":"org.http4s:http4s-server_3","fixedVersion":"0.23.2"},{"ecosystem":"Maven","name":"org.http4s:http4s-server_2.10","fixedVersion":null},{"ecosystem":"Maven","name":"org.http4s:http4s-server_2.11","fixedVersion":null},{"ecosystem":"Maven","name":"org.http4s:http4s-server_2.12","fixedVersion":"0.21.27"},{"ecosystem":"Maven","name":"org.http4s:http4s-server_2.12","fixedVersion":"0.22.3"},{"ecosystem":"Maven","name":"org.http4s:http4s-server_2.12","fixedVersion":"0.23.2"},{"ecosystem":"Maven","name":"org.http4s:http4s-server_2.13","fixedVersion":"0.21.27"},{"ecosystem":"Maven","name":"org.http4s:http4s-server_2.13","fixedVersion":"0.22.3"},{"ecosystem":"Maven","name":"org.http4s:http4s-server_2.13","fixedVersion":"0.23.2"}],"fix":null,"references":[{"type":"ADVISORY","url":"https://github.com/http4s/http4s/releases/tag/v0.23.2"},{"type":"FIX","url":"https://github.com/http4s/http4s/security/advisories/GHSA-52cf-226f-rhr6"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-07-09T10:52:20.589461Z"}}