CVE-2021-39185: critical vulnerability in http4s
Default CORS config allows any origin with credentials
Published · Updated
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28Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 9.1epss 0.6%
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/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Affected products
http4s · http4sRelated CVEs — http4s
In the same product, most dangerous first.
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