CVE-2021-32643: medium-severity vulnerability in http4s
StaticFile.fromUrl can leak presence of a directory
Published · Updated
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13Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 5.8epss 1.4%
Http4s is a Scala interface for HTTP services. `StaticFile.fromUrl` can leak the presence of a directory on a server when the `URL` scheme is not `file://`, and the URL points to a fetchable resource under its scheme and authority. The function returns `F[None]`, indicating no resource, if `url.getFile` is a directory, without first checking the scheme or authority of the URL. If a URL connection to the scheme and URL would return a stream, and the path in the URL exists as a directory on the server, the presence of the directory on the server could be inferred from the 404 response. The contents and other metadata about the directory are not exposed. This affects http4s versions: 0.21.7 through 0.21.23, 0.22.0-M1 through 0.22.0-M8, 0.23.0-M1, and 1.0.0-M1 through 1.0.0-M22. The [patch](https://github.com/http4s/http4s/commit/52e1890665410b4385e37b96bc49c5e3c708e4e9) is available in the following versions: v0.21.24, v0.22.0-M9, v0.23.0-M2, v1.0.0-M23. As a workaround users can avoid calling `StaticFile.fromUrl` with non-file URLs.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:N
Affected products
http4s · http4sRelated CVEs — http4s
In the same product, most dangerous first.
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