CVE-2024-55875 is a critical-severity (CVSS 9.8) Information Exposure vulnerability in org.http4k:http4k-format-xml. 2 public exploit references exist, so weaponization risk is real. A fix is available for org.http4k:http4k-format-xml — see the affected versions and patch details below.
http4k has a potential XXE (XML External Entity Injection) vulnerability
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- A successful exploit gives an attacker total control of the affected component, not partial access.
Exploitation and automatability from CISA’s SSVC triage for CVE-2024-55875.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2024-55875 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 377,238 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
org.http4k:http4k-format-xmlReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Maven packages — download data is not available via public APIs for these ecosystems.
Description
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 <!DOCTYPE> 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 <!DOCTYPE> is now rejected at parse time.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | org.http4k:http4k-format-xml | all versions | 6.50.0.0org.http4k:http4k-format-xml:6.50.0.0 |
Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.http4k:http4k-format-xml, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update org.http4k:http4k-format-xml to 6.50.0.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2024-55875 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2024-55875 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2024-55875. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2024-55875 in your dependencies?
O3 Security finds CVE-2024-55875 across Maven dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.