Summary
Workarounds
Avoid processing USPTO patent XML files from untrusted sources. Implement resource limits (memory, CPU time) when processing patent documents.
References
- Fix release: v2.74.0
Impact
The USPTO patent XML parser used the standard xml.sax.parseString() without protection against XML External Entity (XXE) attacks. An attacker could craft malicious USPTO patent XML files with external entity references that could:
- Read arbitrary files from the server filesystem
- Perform Server-Side Request Forgery (SSRF) attacks
- Cause denial of service through entity expansion (Billion Laughs attack)
The vulnerability affects three USPTO patent format parsers: ICE (v4.x), Grant v2.5, and Application v1.x.
CVE-2026-44020 has a CVSS score of 7.5 (High). The vector is network-reachable, no privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (2.74.0); upgrading removes the vulnerable code path.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
Remediation advice
Fixed in version 2.74.0. The parser now uses defusedxml.sax.make_parser() with secure configuration that blocks external entity resolution (feature_external_ges=False, feature_external_pes=False) while allowing DTD declarations required by USPTO files. This prevents XXE attacks while maintaining compatibility with the USPTO XML format.
Frequently Asked Questions
- What is CVE-2026-44020? CVE-2026-44020 is a high-severity security vulnerability in docling (pip), affecting versions >= 2.13.0, < 2.74.0. It is fixed in 2.74.0.
- How severe is CVE-2026-44020? CVE-2026-44020 has a CVSS score of 7.5 (High). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
- Which versions of docling are affected by CVE-2026-44020? docling (pip) versions >= 2.13.0, < 2.74.0 is affected.
- Is there a fix for CVE-2026-44020? Yes. CVE-2026-44020 is fixed in 2.74.0. Upgrade to this version or later.
- Is CVE-2026-44020 exploitable, and should I be worried? Whether CVE-2026-44020 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether CVE-2026-44020 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix CVE-2026-44020? Upgrade
doclingto 2.74.0 or later.