CVE-2026-41839: Spring Framework Spring Framework Escalation Vulnerability

MODERATE
Advisory Identifier: GHSA-4hfh-6x8g-gwpp
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CVSS 4.2
CWE-384
Published
Advisory Summary

CVE-2026-41839 is a MODERATE (CVSS 4.2) spring framework escalation vulnerability (CWE-384: Session Fixation) affecting Spring Framework libraries in the Maven ecosystem. The issue involves spring framework escalation via session fixation in webflux. Remediation is available by upgrading affected packages to version 7.0.8, 6.2.19.

CVE-2026-41839 at a Glance

CVE Identifier CVE-2026-41839
GHSA Identifier GHSA-4hfh-6x8g-gwpp
Severity MODERATE
CVSS v3.1 Base Score 4.2
CWE Classification CWE-384: Session Fixation
Affected Product Spring Framework
Package Ecosystem Maven
Published Date
Last Updated

Security Impact

CVSS: 4.2

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

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

How to Fix CVE-2026-41839

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

org.springframework:spring-webflux fixed: 7.0.8 
<dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-webflux</artifactId>
    <version>7.0.8</version>
</dependency>
org.springframework:spring-webflux fixed: 6.2.19 
<dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-webflux</artifactId>
    <version>6.2.19</version>
</dependency>
org.springframework:spring-webflux fixed: Latest secure release 
<dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-webflux</artifactId>
    <version>Latest secure release</version>
</dependency>
org.springframework:spring-webflux fixed: Latest secure release 
<dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-webflux</artifactId>
    <version>Latest secure release</version>
</dependency>
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 -Dincludes=org.springframework

How to Check if You Are Affected

To determine whether your Java application is affected by CVE-2026-41839, inspect your build dependencies using the Maven Dependency Plugin:

mvn dependency:tree -Dincludes=org.springframework

Analyze the terminal output to locate any version of Spring Framework in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 7.0.8), your application is affected.

Note: The mvn dependency:tree -Dincludes=org.springframework 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 Spring Framework, 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

A WebFlux application with a compromised subdomain (for example, compromised via cross-site scripting (XSS)) is vulnerable to an escalation attack exchanging a known session ID for that of an authenticated user. Affected versions: Spring Framework 7.0.0 through 7.0.7; 6.2.0 through 6.2.18; 6.1.0 through 6.1.27; 5.3.0 through 5.3.48.

CVE-2026-41839 Affected Spring Framework Versions

4 component(s)
Fixed Versions:
7.0.86.2.19
Product / Package Ecosystem Affected Versions Fixed Version
org.springframework:spring-webflux
maven/org.springframework/spring-webflux
Maven
≥ 7.0.0
< 7.0.8
7.0.8
org.springframework:spring-webflux
maven/org.springframework/spring-webflux
Maven
≥ 6.2.0
< 6.2.19
6.2.19
org.springframework:spring-webflux
maven/org.springframework/spring-webflux
Maven
≥ 6.1.0
≤ 6.1.21
org.springframework:spring-webflux
maven/org.springframework/spring-webflux
Maven
≤ 5.3.39

References

NVD — CVE-2026-41839 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-41839
Spring Framework Source Repository REPOSITORY
https://github.com/spring-projects/spring-framework/issues/36742
Spring Framework Source Repository REPOSITORY
https://github.com/spring-projects/spring-framework/issues/36743
Security Fix Commit FIX COMMIT
https://github.com/spring-projects/spring-framework/commit/b8ddd2c690fe3f00bb5e3d9f913a37504aab49a0
Security Fix Commit FIX COMMIT
https://github.com/spring-projects/spring-framework/commit/d72da90d3a562632e2b565113813f7b4a31f8717
Spring Framework Source Repository REPOSITORY
https://github.com/spring-projects/spring-framework
Spring Framework Release RELEASE
https://github.com/spring-projects/spring-framework/releases/tag/v6.2.19
Spring Framework Release RELEASE
https://github.com/spring-projects/spring-framework/releases/tag/v7.0.8
Spring Framework Security Information SECURITY
https://spring.io/security/cve-2026-41839

Frequently Asked Questions

What is CVE-2026-41839?
CVE-2026-41839 is a security vulnerability in Spring Framework involving Spring Framework Escalation via Session Fixation in WebFlux under CWE-384: Session Fixation.
Which Spring Framework versions are affected?
Affected versions include releases prior to 7.0.8, 6.2.19 across affected packages: org.springframework:spring-webflux.
What version fixes CVE-2026-41839?
Upgrading to 7.0.8, 6.2.19 (or the latest patched release for your respective branch) resolves the vulnerability.
Is spring-webflux affected?
Yes, org.springframework:spring-webflux is affected in releases prior to 7.0.8, 6.2.19, Latest secure release. Upgrade your dependency to 7.0.8, 6.2.19, Latest secure release or later.
What is the CVSS score of CVE-2026-41839?
CVE-2026-41839 has a CVSS v3.1 base score of 4.2 (MODERATE) with vector string CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N.
What CWE is associated with CVE-2026-41839?
CVE-2026-41839 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-2026-41839?
Run the dependency tree command: 'mvn dependency:tree -Dincludes=org.springframework'. 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-4hfh-6x8g-gwpp",
  "modified" : "2026-07-30T15:16:57Z",
  "published" : "2026-06-09T06:31:57Z",
  "aliases" : [ "CVE-2026-41839" ],
  "summary" : "Spring Framework Escalation via Session Fixation in WebFlux",
  "details" : "A WebFlux application with a compromised subdomain (for example, compromised via cross-site scripting (XSS)) is vulnerable to an escalation attack exchanging a known session ID for that of an authenticated user.\n\nAffected versions:\nSpring Framework 7.0.0 through 7.0.7; 6.2.0 through 6.2.18; 6.1.0 through 6.1.27; 5.3.0 through 5.3.48.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Maven",
      "name" : "org.springframework:spring-webflux"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "7.0.0"
      }, {
        "fixed" : "7.0.8"
      } ]
    } ],
    "database_specific" : {
      "last_known_affected_version_range" : "<= 7.0.7"
    }
  }, {
    "package" : {
      "ecosystem" : "Maven",
      "name" : "org.springframework:spring-webflux"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "6.2.0"
      }, {
        "fixed" : "6.2.19"
      } ]
    } ],
    "database_specific" : {
      "last_known_affected_version_range" : "<= 6.2.18"
    }
  }, {
    "package" : {
      "ecosystem" : "Maven",
      "name" : "org.springframework:spring-webflux"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "6.1.0"
      }, {
        "last_affected" : "6.1.21"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "Maven",
      "name" : "org.springframework:spring-webflux"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "last_affected" : "5.3.39"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-41839"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/spring-projects/spring-framework/issues/36742"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/spring-projects/spring-framework/issues/36743"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/spring-projects/spring-framework/commit/b8ddd2c690fe3f00bb5e3d9f913a37504aab49a0"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/spring-projects/spring-framework/commit/d72da90d3a562632e2b565113813f7b4a31f8717"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/spring-projects/spring-framework"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/spring-projects/spring-framework/releases/tag/v6.2.19"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/spring-projects/spring-framework/releases/tag/v7.0.8"
  }, {
    "type" : "WEB",
    "url" : "https://spring.io/security/cve-2026-41839"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-384" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-07-30T15:16:57Z",
    "nvd_published_at" : "2026-06-09T05:16:35Z"
  }
}