CVE-2026-82617: Software Security Vulnerability Vulnerability

CRITICAL
Advisory Identifier: GHSA-f3wj-w3qw-rw57
CWE-1333
Published
Advisory Summary

CVE-2026-82617 is a CRITICAL security vulnerability vulnerability (CWE-1333: Inefficient Regular Expression Complexity) affecting Software libraries in the Maven ecosystem. The weakness occurs when the product uses a regular expression with a worst-case computational complexity that is inefficient and possibly exponential.. Remediation is available in the latest vendor maintenance releases.

CVE-2026-82617 at a Glance

CVE Identifier CVE-2026-82617
GHSA Identifier GHSA-f3wj-w3qw-rw57
Severity CRITICAL
CVSS v3.1 Base Score N/A
CWE Classification CWE-1333: Inefficient Regular Expression Complexity
Affected Product Software
Package Ecosystem Maven
Published Date
Last Updated

How to Fix CVE-2026-82617

To remediate this vulnerability, upgrade all affected Software dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release:

mvn dependency:tree

How to Check if You Are Affected

To determine whether your Java application is affected by CVE-2026-82617, inspect your build dependencies using the Maven Dependency Plugin:

mvn dependency:tree

Analyze the terminal output to locate any version of Software in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than the patched release), your application is affected.

Note: The mvn dependency:tree command inspects the resolved dependency graph declared in your project's POM files; it does not perform automated security scanning or inspect runtime dynamic classpaths. Always verify runtime container classpaths and shaded JARs.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-1333: Inefficient Regular Expression Complexity, where the product uses a regular expression with a worst-case computational complexity that is inefficient and possibly exponential. In Software, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

The two built-in name-finder patterns exposed by opennlp.tools.namefind.RegexNameFinderFactory - DEFAULT_REGEX_NAME_FINDER.EMAIL and DEFAULT_REGEX_NAME_FINDER.URL - contain ambiguous nested quantifiers. An application that obtains these finders through RegexNameFinderFactory.getDefaultRegexNameFinders(...) and then applies them to untrusted text through RegexNameFinder.find(String[]) or RegexNameFinder.find(String) can be driven into super-linear backtracking or into unbounded matcher recursion by a small crafted input. For the EMAIL pattern, a long run of local-part characters that is never followed by an @ forces the matcher to re-scan to end-of-input from every starting offset. Cost grows quadratically with input length: an input of approximately 32 KB consumes several seconds of CPU in a single find() call and returns no match, and each doubling of the input multiplies the cost roughly four-fold. For the URL pattern, the query-string sub-expression nests a capturing repetition inside an outer repetition. The JDK matcher recurses once per query token, so an input of approximately 4 KB containing many &-separated tokens exhausts the thread stack and causes java.lang.StackOverflowError to propagate out of find(), terminating the calling thread. On a thread created with a smaller stack (for example -Xss512k, typical of server worker pools) approximately 1 KB is sufficient. In both cases an attacker who can supply text for analysis can convert a single request into seconds to minutes of pinned CPU, or into an abrupt thread death, denying service to the embedding application. No authentication, special configuration, or model file is required beyond the application having selected one of the two built-in finders. This issue affects Apache OpenNLP: from 2.0.0 through 2.5.11; from 3.0.0-M1 through 3.0.0-M5. Users are recommended to upgrade to version 2.5.12, or to 3.0.0-M6 for users tracking the 3.0.0 milestone line, which fix the issue.

References

Frequently Asked Questions

What is CVE-2026-82617?
CVE-2026-82617 is a security vulnerability in Software classified as a security vulnerability vulnerability under CWE-1333: Inefficient Regular Expression Complexity.
Which Software versions are affected?
Affected versions include releases prior to current release patches.
What version fixes CVE-2026-82617?
Upgrading to current release patches (or the latest patched release for your respective branch) resolves the vulnerability.
What CWE is associated with CVE-2026-82617?
CVE-2026-82617 is classified under CWE-1333: Inefficient Regular Expression Complexity (The product uses a regular expression with a worst-case computational complexity that is inefficient and possibly exponential.).
How can I check Maven dependencies for CVE-2026-82617?
Run the dependency tree command: 'mvn dependency:tree'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-f3wj-w3qw-rw57",
  "modified" : "2026-09-11T21:31:17Z",
  "published" : "2026-09-11T18:31:27Z",
  "aliases" : [ "CVE-2026-82617" ],
  "details" : "The two built-in name-finder patterns exposed by\nopennlp.tools.namefind.RegexNameFinderFactory - DEFAULT_REGEX_NAME_FINDER.EMAIL\nand DEFAULT_REGEX_NAME_FINDER.URL - contain ambiguous nested quantifiers. An\napplication that obtains these finders through\nRegexNameFinderFactory.getDefaultRegexNameFinders(...) and then applies them to\nuntrusted text through RegexNameFinder.find(String[]) or RegexNameFinder.find(String)\ncan be driven into super-linear backtracking or into unbounded matcher recursion by a\nsmall crafted input.\n\n\n\n\n\nFor the EMAIL pattern, a long run of local-part characters that is never followed by an\n@ forces the matcher to re-scan to end-of-input from every starting offset. Cost grows\nquadratically with input length: an input of approximately 32 KB consumes several seconds\nof CPU in a single find() call and returns no match, and each doubling of the input\nmultiplies the cost roughly four-fold.\n\n\n\n\n\nFor the URL pattern, the query-string sub-expression nests a capturing repetition inside\nan outer repetition. The JDK matcher recurses once per query token, so an input of\napproximately 4 KB containing many &-separated tokens exhausts the thread stack and\ncauses java.lang.StackOverflowError to propagate out of find(), terminating the\ncalling thread. On a thread created with a smaller stack (for example -Xss512k, typical\nof server worker pools) approximately 1 KB is sufficient.\n\n\n\n\n\nIn both cases an attacker who can supply text for analysis can convert a single request\ninto seconds to minutes of pinned CPU, or into an abrupt thread death, denying service to\nthe embedding application. No authentication, special configuration, or model file is\nrequired beyond the application having selected one of the two built-in finders.\n\n\n\n\n\nThis issue affects Apache OpenNLP: from 2.0.0 through 2.5.11; from 3.0.0-M1 through\n3.0.0-M5.\n\n\n\n\n\n\n\n\n\nUsers are recommended to upgrade to version 2.5.12, or to 3.0.0-M6 for users tracking the\n3.0.0 milestone line, which fix the issue.",
  "severity" : [ {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X"
  } ],
  "affected" : [ ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-82617"
  }, {
    "type" : "WEB",
    "url" : "https://lists.apache.org/thread/spzhcxxszqdpppg70m1zz2l3mv29mhl3"
  }, {
    "type" : "WEB",
    "url" : "http://www.openwall.com/lists/oss-security/2026/09/11/10"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-1333" ],
    "severity" : "CRITICAL",
    "github_reviewed" : false,
    "github_reviewed_at" : null,
    "nvd_published_at" : "2026-09-11T18:16:59Z"
  }
}