CVE-2021-39185
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.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.59%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
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.
- CVSS 3.1
- 9.1 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
- EPSS
- 0.59% probability · 47th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-346
- Affected
- typelevel/http4s
- Source
- security-advisories@github.com
References
- https://github.com/http4s/http4s/releases/tag/v0.23.2Third Party Advisory
- https://github.com/http4s/http4s/security/advisories/GHSA-52cf-226f-rhr6Patch, Third Party Advisory
- https://github.com/http4s/http4s/releases/tag/v0.23.2Third Party Advisory
- https://github.com/http4s/http4s/security/advisories/GHSA-52cf-226f-rhr6Patch, Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.