CVE-2021-39185

Default CORS config allows any origin with credentials

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.

Category

9.1
CVSS
Severity: Critical
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.14%
Third-Party Advisory github.com Third-Party Advisory github.com
Affected: http4s http4s
Published at:
Updated at:

References

Link Tags
https://github.com/http4s/http4s/security/advisories/GHSA-52cf-226f-rhr6 third party advisory patch
https://github.com/http4s/http4s/releases/tag/v0.23.2 third party advisory

Frequently Asked Questions

What is the severity of CVE-2021-39185?
CVE-2021-39185 has been scored as a critical severity vulnerability.
How to fix CVE-2021-39185?
To fix CVE-2021-39185, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-39185 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-39185 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-39185?
CVE-2021-39185 affects http4s http4s.
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