CVE-2026-81827: Software Security Vulnerability Vulnerability

MODERATE
Advisory Identifier: GHSA-3hq8-r684-4qwf
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CWE-20
Published
Advisory Summary

CVE-2026-81827 is a MODERATE security vulnerability vulnerability (CWE-20: Improper Input Validation) affecting Software libraries in the Maven ecosystem. The weakness occurs when the product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.. Remediation is available in the latest vendor maintenance releases.

CVE-2026-81827 at a Glance

CVE Identifier CVE-2026-81827
GHSA Identifier GHSA-3hq8-r684-4qwf
Severity MODERATE
CVSS v3.1 Base Score N/A
CWE Classification CWE-20: Improper Input Validation
Affected Product Software
Package Ecosystem Maven
Published Date
Last Updated

How to Fix CVE-2026-81827

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-2026-81827, 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-20: Improper Input Validation, where the product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly. 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

Affected versions of Flowintel incorrectly attempted to validate login email addresses by calling Email(email). That does not perform WTForms field validation; it merely constructs a validator object. Consequently, malformed attacker-controlled email input could continue through the login process and be written to security-relevant logs. The vulnerable code inserted the supplied email into both a warning log and the custom audit logger. Since CR/LF characters were not escaped, an unauthenticated attacker could potentially inject additional physical log lines or forge misleading log entries. The patch corrects the validation call to Email()(form, form.email), changes the standard logging call to parameterized logging, and introduces _sanitize_log_fragment() so carriage returns and line feeds are encoded instead of creating new records. Version impacted >=3.3.0

References

NVD — CVE-2026-81827 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-81827
Security Fix Commit FIX COMMIT
https://github.com/flowintel/flowintel/commit/660b4cc405055a794f157d3e4612520f12fe65bf

Frequently Asked Questions

What is CVE-2026-81827?
CVE-2026-81827 is a security vulnerability in Software classified as a security vulnerability vulnerability under CWE-20: Improper Input Validation.
Which Software versions are affected?
Affected versions include releases prior to current release patches.
What version fixes CVE-2026-81827?
Upgrading to current release patches (or the latest patched release for your respective branch) resolves the vulnerability.
What CWE is associated with CVE-2026-81827?
CVE-2026-81827 is classified under CWE-20: Improper Input Validation (The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.).
How can I check Maven dependencies for CVE-2026-81827?
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-3hq8-r684-4qwf",
  "modified" : "2026-08-27T18:32:30Z",
  "published" : "2026-08-27T18:32:30Z",
  "aliases" : [ "CVE-2026-81827" ],
  "details" : "Affected versions of Flowintel incorrectly attempted to validate login email addresses by calling Email(email). That does not perform WTForms field validation; it merely constructs a validator object.\n\n\nConsequently, malformed attacker-controlled email input could continue through the login process and be written to security-relevant logs. The vulnerable code inserted the supplied email into both a warning log and the custom audit logger. Since CR/LF characters were not escaped, an unauthenticated attacker could potentially inject additional physical log lines or forge misleading log entries.\n\nThe patch corrects the validation call to Email()(form, form.email), changes the standard logging call to parameterized logging, and introduces _sanitize_log_fragment() so carriage returns and line feeds are encoded instead of creating new records.\n\nVersion impacted >=3.3.0",
  "severity" : [ {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/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-2026-81827"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/flowintel/flowintel/commit/660b4cc405055a794f157d3e4612520f12fe65bf"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-20" ],
    "severity" : "MODERATE",
    "github_reviewed" : false,
    "github_reviewed_at" : null,
    "nvd_published_at" : "2026-08-27T17:21:05Z"
  }
}