CVE-2026-61741

http4s-scala-xml has an XML External Entity (XXE) processing issue

Published Sep 24, 2026 CVSS 3.1 · 9.3 Critical EPSS < 1% KEV · Not listed
Description
http4s-scala-xml provides `EntityDecoder[F, scala.xml.Elem]` instances that parse XML message bodies. Prior to versions 0.24.1 and 1.0.0-M39, these decoders used a `javax.xml.parsers.SAXParserFactory` obtained from `SAXParserFactory.newInstance` without any security configuration. With the JDK's default settings, the parser resolves DOCTYPE declarations, external general and parameter entities, and external DTDs.An application that uses these decoders to parse untrusted XML is vulnerable to XML External Entity (XXE) attacks. An attacker can craft a request that discloses local files readable by the service process, performs server-side request forgery (SSRF) against internal network resources, and/or causes denial of service through entity expansion. Versions 0.24.1 and 1.0.0-M39 fix the issue.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Github GHSA Github GHSA GHSA-cjx3-73hr-rpw7 http4s-scala-xml has an XML External Entity (XXE) processing issue
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Http4s
Http4s http4s-scala-xml
Vendors & Products Http4s
Http4s http4s-scala-xml
Type Values Removed Values Added
Description http4s-scala-xml provides `EntityDecoder[F, scala.xml.Elem]` instances that parse XML message bodies. Prior to versions 0.24.1 and 1.0.0-M39, these decoders used a `javax.xml.parsers.SAXParserFactory` obtained from `SAXParserFactory.newInstance` without any security configuration. With the JDK's default settings, the parser resolves DOCTYPE declarations, external general and parameter entities, and external DTDs.An application that uses these decoders to parse untrusted XML is vulnerable to XML External Entity (XXE) attacks. An attacker can craft a request that discloses local files readable by the service process, performs server-side request forgery (SSRF) against internal network resources, and/or causes denial of service through entity expansion. Versions 0.24.1 and 1.0.0-M39 fix the issue.
Title http4s-scala-xml has an XML External Entity (XXE) processing issue
Weaknesses CWE-611
References
Metrics cvssV3_1

{'score': 9.3, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:L'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
Sep 29, 2026, 3:02 AM
Reserved
Jul 10, 2026, 6:59 PM
Status
Deferred
Published
Sep 24, 2026, 6:17 PM
Modified
Sep 30, 2026, 7:57 PM