CVE-2026-40682
9.1 · CRITICALOverview
CVE-2026-40682 is a critical-severity vulnerability affecting apache opennlp. It was published on May 4, 2026 and has a CVSS 3.1 base score of 9.1 (CRITICAL).
This vulnerability has a CVSS 3.1 base score of 9.1, rated CRITICAL. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
Technical Description
XML External Entity (XXE) via Unsanitized Dictionary Parsing in Apache OpenNLP DictionaryEntryPersistor
Versions Affected: before 2.5.9, before 3.0.0-M3
Description: The DictionaryEntryPersistor class initializes a static SAXParserFactory at class-load time without enabling FEATURE_SECURE_PROCESSING or disabling DTD processing. When create(InputStream, EntryInserter) is invoked, the only feature set on the XMLReader is namespace support — external entity resolution and DOCTYPE declarations remain fully enabled. An attacker who can supply a crafted dictionary file (e.g., a stop-word list or domain dictionary) containing a malicious DOCTYPE declaration can trigger local file disclosure via file:// entity references or server-side request forgery via http:// entity references during SAX parsing, before the application processes a single dictionary entry. This is inconsistent with the project's own XmlUtil.createSaxParser() helper, which correctly sets FEATURE_SECURE_PROCESSING and dis
Remediation
Check the references section for vendor advisories and patches from apache. Update opennlp to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
| Vendor | Product | Versions | Status |
|---|---|---|---|
| apache | opennlp | >= 0, < 2.5.9 | Affected |
Frequently Asked Questions
What is CVE-2026-40682?
CVE-2026-40682 is a critical-severity vulnerability affecting apache opennlp. It was published on May 4, 2026 and has a CVSS 3.1 base score of 9.1 (CRITICAL).
How severe is CVE-2026-40682?
This vulnerability has a CVSS 3.1 base score of 9.1, rated CRITICAL. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
How do I fix or remediate CVE-2026-40682?
Check the references section for vendor advisories and patches from apache. Update opennlp to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2026-40682?
CyberStrike's AI-powered security agents can automatically detect CVE-2026-40682 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
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