CVE-2026-6684: Software Security Vulnerability Vulnerability

MODERATE
Advisory Identifier: GHSA-vhc7-qgwj-vx6v
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CVSS 4.6
CWE-835
Published
Advisory Summary

CVE-2026-6684 is a MODERATE (CVSS 4.6) security vulnerability vulnerability (CWE-835: Loop with Unreachable Exit Condition ('Infinite Loop')) affecting Software libraries in the Maven ecosystem. The weakness occurs when the product contains an iteration or loop with an exit condition that cannot be reached, i.e., an infinite loop.. Remediation is available in the latest vendor maintenance releases.

CVE-2026-6684 at a Glance

CVE Identifier CVE-2026-6684
GHSA Identifier GHSA-vhc7-qgwj-vx6v
Severity MODERATE
CVSS v3.1 Base Score 4.6
CWE Classification CWE-835: Loop with Unreachable Exit Condition ('Infinite Loop')
Affected Product Software
Package Ecosystem Maven
Published Date
Last Updated

Security Impact

CVSS: 4.6

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H).

Attack Vector Physical (AV:P)
Attack Complexity Low (AC:L)
Privileges Required None (PR:N)
User Interaction None (UI:N)
Scope Unchanged (S:U)
Confidentiality None (C:N)
Integrity None (I:N)
Availability High (A:H)

How to Fix CVE-2026-6684

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-2026-6684, 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-835: Loop with Unreachable Exit Condition ('Infinite Loop'), where the product contains an iteration or loop with an exit condition that cannot be reached, i.e., an infinite loop. 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

FatFs prior to R0.16 that use GPT scanning with 'FF_LBA64 = 1' contains an issue where an unbounded loop count derived from GPT header field GPTH_PtNum, enabling extremely long or effectively infinite mount-time scans. This maps to CWE-835 (Loop with Unreachable Exit Condition). Estimated CVSS v3.1 vector: CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H (4.6, Medium). The estimated CISA SSVC vectors are Exploitation: PoC, Technical Impact: Partial.

References

NVD — CVE-2026-6684 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-6684
elm-chan.org/fsw/ff WEB
https://elm-chan.org/fsw/ff
Software Source Repository REPOSITORY
https://github.com/runZeroInc/vulns-2026-fatfs-chance
www.runzero.com/blog/fatfs-bugs WEB
https://www.runzero.com/blog/fatfs-bugs
www.runzero.com/advisories/fatfs-gp... WEB
https://www.runzero.com/advisories/fatfs-gpt-scan-loop-dos-cve-2026-6684

Frequently Asked Questions

What is CVE-2026-6684?
CVE-2026-6684 is a security vulnerability in Software classified as a security vulnerability vulnerability under CWE-835: Loop with Unreachable Exit Condition ('Infinite Loop').
Which Software versions are affected?
Affected versions include releases prior to current release patches.
What version fixes CVE-2026-6684?
Upgrading to current release patches (or the latest patched release for your respective branch) resolves the vulnerability.
What is the CVSS score of CVE-2026-6684?
CVE-2026-6684 has a CVSS v3.1 base score of 4.6 (MODERATE) with vector string CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.
What CWE is associated with CVE-2026-6684?
CVE-2026-6684 is classified under CWE-835: Loop with Unreachable Exit Condition ('Infinite Loop') (The product contains an iteration or loop with an exit condition that cannot be reached, i.e., an infinite loop.).
How can I check Maven dependencies for CVE-2026-6684?
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
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-vhc7-qgwj-vx6v",
  "modified" : "2026-07-01T15:35:20Z",
  "published" : "2026-07-01T15:35:20Z",
  "aliases" : [ "CVE-2026-6684" ],
  "details" : "FatFs prior to R0.16 that use GPT scanning with 'FF_LBA64 = 1' contains an issue where an unbounded loop count derived from GPT header field GPTH_PtNum, enabling extremely long or effectively infinite mount-time scans. This maps to CWE-835 (Loop with Unreachable Exit Condition). Estimated CVSS v3.1 vector: CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H (4.6, Medium). The estimated CISA SSVC vectors are Exploitation: PoC, Technical Impact: Partial.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"
  } ],
  "affected" : [ ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-6684"
  }, {
    "type" : "WEB",
    "url" : "https://elm-chan.org/fsw/ff"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/runZeroInc/vulns-2026-fatfs-chance"
  }, {
    "type" : "WEB",
    "url" : "https://www.runzero.com/advisories/fatfs-gpt-scan-loop-dos-cve-2026-6684"
  }, {
    "type" : "WEB",
    "url" : "https://www.runzero.com/blog/fatfs-bugs"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-835" ],
    "severity" : "MODERATE",
    "github_reviewed" : false,
    "github_reviewed_at" : null,
    "nvd_published_at" : "2026-07-01T15:17:12Z"
  }
}