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TI-2024-36944 Aliases CVE-2024-55875GHSA-7mj5-hjjj-8rgw

http4k has a potential XXE (XML External Entity Injection) vulnerability

Priority HIGH 82CWE-200Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Information disclosure
Confidentiality · integrity · availability
High · High · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub. Impact type from CWE-200.

Summary

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.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.01905 79th percentileScored 2026-11-07
Fix Fixed http4k (http4k): 6.50.0.0org.http4k:http4k-format-xml (Maven): 6.50.0.0

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
Yes
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
http4khttp4kbefore 6.50.0.06.50.0.0Patch availableCNA
—org.http4k:http4k-format-xml (Maven)before 6.50.0.06.50.0.0Patch availableGHSA-7mj5-hjjj-8rgw
  • http4k Vendorhttp4k Affected before 6.50.0.0 Fixed in 6.50.0.0 Patch available CNA
  • org.http4k:http4k-format-xml (Maven) Vendor— Affected before 6.50.0.0 Fixed in 6.50.0.0 Patch available GHSA-7mj5-hjjj-8rgw

Remediation

  • Fix · CNA http4k (http4k) Fixed in 6.50.0.0
  • Fix · GHSA-7mj5-hjjj-8rgw org.http4k:http4k-format-xml (Maven) Fixed in 6.50.0.0 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2024-55875
  2. 2026-10-03 Alias added: GHSA-7mj5-hjjj-8rgw

References

Advisory 1

Other 4

  • TI-2026-83683 Missing body integrity check in http4k Digest auth-int CVSS 4.0HIGH 8.2
  • TI-2026-38700 http4k: Unbounded gzip decompression in `ServerFilters.GZip` / `RequestFilters.GunZip` allowed memory-exhaustion DoS CVSS 3.1HIGH 7.5
  • TI-2026-39062 http4k: `DigestAuthProvider.verify` did not bind to request URI CVSS 3.1HIGH 8.1
  • TI-2026-64972 http4k before 6.48.0.0 Digest Authentication Replay Protection Bypass CVSS 4.0HIGH 8.2
  • TI-2026-64881 http4k before 6.48.0.0 Cookie Scoping Bypass via BasicCookieStorage CVSS 4.0HIGH 8.3
  • TI-2026-83682 Path traversal in http4k ThymeleafTemplates lets attackers read files CVSS 4.0HIGH 8.2
See all 8 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences