CVE-2026-81826: Software Security Vulnerability Vulnerability

CRITICAL
Advisory Identifier: GHSA-m2jr-93w5-4c48
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CWE-384
Published
Advisory Summary

CVE-2026-81826 is a CRITICAL security vulnerability vulnerability (CWE-384: Session Fixation) affecting Software libraries in the Maven ecosystem. The weakness occurs when authenticating a user, or otherwise establishing a new user session, without invalidating any existing session identifier gives an attacker the opportunity to steal authenticated sessions.. Remediation is available in the latest vendor maintenance releases.

CVE-2026-81826 at a Glance

CVE Identifier CVE-2026-81826
GHSA Identifier GHSA-m2jr-93w5-4c48
Severity CRITICAL
CVSS v3.1 Base Score N/A
CWE Classification CWE-384: Session Fixation
Affected Product Software
Package Ecosystem Maven
Published Date
Last Updated

How to Fix CVE-2026-81826

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-2026-81826, 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-384: Session Fixation, where authenticating a user, or otherwise establishing a new user session, without invalidating any existing session identifier gives an attacker the opportunity to steal authenticated sessions. 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 do not revoke existing authenticated sessions when a user’s password is changed. This means that if an attacker already possesses a valid session—for example, from prior access or a stolen session token—the victim changing their password does not terminate that attacker’s access. The session remains usable until it expires naturally. The upstream commit describes this directly as: “session keeps working until it expires.” The fix detects password changes and explicitly invokes _invalidate_user_sessions(user.id) after the database update. This is applied in both edit_user_core() and admin_edit_user_core(). Version impacted >=3.3.0

References

NVD — CVE-2026-81826 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-81826
Security Fix Commit FIX COMMIT
https://github.com/flowintel/flowintel/commit/e46e075b8f28212800fc57ead0a7f9a2921bfff0.patch

Frequently Asked Questions

What is CVE-2026-81826?
CVE-2026-81826 is a security vulnerability in Software classified as a security vulnerability vulnerability under CWE-384: Session Fixation.
Which Software versions are affected?
Affected versions include releases prior to current release patches.
What version fixes CVE-2026-81826?
Upgrading to current release patches (or the latest patched release for your respective branch) resolves the vulnerability.
What CWE is associated with CVE-2026-81826?
CVE-2026-81826 is classified under CWE-384: Session Fixation (Authenticating a user, or otherwise establishing a new user session, without invalidating any existing session identifier gives an attacker the opportunity to steal authenticated sessions.).
How can I check Maven dependencies for CVE-2026-81826?
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-m2jr-93w5-4c48",
  "modified" : "2026-08-27T18:32:30Z",
  "published" : "2026-08-27T18:32:30Z",
  "aliases" : [ "CVE-2026-81826" ],
  "details" : "Affected versions of Flowintel do not revoke existing authenticated sessions when a user’s password is changed.\n\n\nThis means that if an attacker already possesses a valid session—for example, from prior access or a stolen session token—the victim changing their password does not terminate that attacker’s access. The session remains usable until it expires naturally. The upstream commit describes this directly as:\n\n\n“session keeps working until it expires.”\n\nThe fix detects password changes and explicitly invokes _invalidate_user_sessions(user.id) after the database update. This is applied in both edit_user_core() and admin_edit_user_core().\n\nVersion impacted >=3.3.0",
  "severity" : [ {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/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-2026-81826"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/flowintel/flowintel/commit/e46e075b8f28212800fc57ead0a7f9a2921bfff0.patch"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-384" ],
    "severity" : "CRITICAL",
    "github_reviewed" : false,
    "github_reviewed_at" : null,
    "nvd_published_at" : "2026-08-27T17:21:05Z"
  }
}