CVE-2026-43827: CWE-384 Session Fixation in Apache Software Foundation Apache Shiro
Apache Shiro versions 1.0, 3.0.0-alpha, and up to 2.1.0 have a session fixation vulnerability in their default configurations. The issue occurs because existing sessions are not invalidated nor replaced with new session IDs upon successful login. This vulnerability allows an attacker to fixate a user's session ID, potentially leading to unauthorized session use. The vulnerability is fixed in Apache Shiro versions 2.1.1 and 3.0.0-alpha-2 or later.
AI Analysis
Technical Summary
Apache Shiro contains a session fixation vulnerability (CWE-384) in default configurations affecting versions 1.0, 3.0.0-alpha, and all versions up to 2.1.0. The vulnerability arises because when a session already exists, it is not invalidated or replaced with a new session ID upon successful login. This behavior can allow an attacker to reuse a fixed session ID to hijack a user's session. The issue is resolved by upgrading to Apache Shiro 2.1.1 or 3.0.0-alpha-2 or later, where session invalidation or regeneration on login is properly implemented.
Potential Impact
The vulnerability allows an attacker to perform session fixation attacks by forcing a user to use a known session ID, potentially leading to unauthorized access or session hijacking. The CVSS 4.0 score is 5.9 (medium severity), indicating a moderate risk with network attack vector, low attack complexity, and requiring user interaction and partial attack complexity. There are no known exploits in the wild at this time.
Mitigation Recommendations
Users should upgrade Apache Shiro to version 2.1.1 or 3.0.0-alpha-2 or later to address this session fixation vulnerability. No other mitigations are indicated. Patch status is confirmed by the vendor's recommended upgrade versions.
CVE-2026-43827: CWE-384 Session Fixation in Apache Software Foundation Apache Shiro
Description
Apache Shiro versions 1.0, 3.0.0-alpha, and up to 2.1.0 have a session fixation vulnerability in their default configurations. The issue occurs because existing sessions are not invalidated nor replaced with new session IDs upon successful login. This vulnerability allows an attacker to fixate a user's session ID, potentially leading to unauthorized session use. The vulnerability is fixed in Apache Shiro versions 2.1.1 and 3.0.0-alpha-2 or later.
CVSS v4.0
Score 5.9medium
Affected software
pkg:maven/org.apache.shiro/shiro-coreRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
Apache Shiro contains a session fixation vulnerability (CWE-384) in default configurations affecting versions 1.0, 3.0.0-alpha, and all versions up to 2.1.0. The vulnerability arises because when a session already exists, it is not invalidated or replaced with a new session ID upon successful login. This behavior can allow an attacker to reuse a fixed session ID to hijack a user's session. The issue is resolved by upgrading to Apache Shiro 2.1.1 or 3.0.0-alpha-2 or later, where session invalidation or regeneration on login is properly implemented.
Potential Impact
The vulnerability allows an attacker to perform session fixation attacks by forcing a user to use a known session ID, potentially leading to unauthorized access or session hijacking. The CVSS 4.0 score is 5.9 (medium severity), indicating a moderate risk with network attack vector, low attack complexity, and requiring user interaction and partial attack complexity. There are no known exploits in the wild at this time.
Mitigation Recommendations
Users should upgrade Apache Shiro to version 2.1.1 or 3.0.0-alpha-2 or later to address this session fixation vulnerability. No other mitigations are indicated. Patch status is confirmed by the vendor's recommended upgrade versions.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- apache
- Date Reserved
- 2026-05-02T22:26:19.626Z
- Cvss Version
- 4.0
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a14b724a5ae1af1aae8513f
Added to database: 05/25/2026, 20:55:00 UTC
Last enriched: 06/30/2026, 23:54:09 UTC
Last updated: 07/31/2026, 19:22:59 UTC
Views: 81
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