CVE-2024-55875: http4k is a functional toolkit for Kotlin HTTP applications. Prior to version 6.50.0.0, there is a potential XXE (XML External Entity Injection) vulnerability…

PriorityP258critical9.8CVSS 3.1

AVNACLPRNUINSUCHIHAH

EPSS

1.90%

77.1th percentile

http4k is a functional toolkit for Kotlin HTTP applications. Prior to version 6.50.0.0, there is a potential XXE (XML External Entity Injection) vulnerability when http4k handling malicious XML contents within requests, which might allow attackers to read local sensitive information on server, trigger Server-side Request Forgery and even execute code under some circumstances. The original fix shipped in v5.41.0.0 / v4.50.0.0 closed the documented external-entity attack class (SSRF, local-file disclosure, code execution) by setting `ACCESS_EXTERNAL_DTD=""`, `ACCESS_EXTERNAL_SCHEMA=""`, and `isExpandEntityReferences=false` on the default `DocumentBuilderFactory`. A residual gap remained: the parser still accepted documents containing `` declarations even though external entity resolution was blocked. This left open billion-laughs-style internal entity expansion DoS attacks against any application using `Body.xml()` or `Document.asXmlDocument()` on untrusted XML. v6.50.0.0 closes this residual by adding `disallow-doctype-decl=true` and `FEATURE_SECURE_PROCESSING=true` to `defaultXmlParsingConfig`. Any document containing a `` is now rejected at parse time.

Affected

1 ranges

Vendor	Product	Version range	Fixed in
http4k	http4k	< 6.50.0.0	6.50.0.0

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