CVE-2026-43827

Name: CVE-2026-43827
Creator: NVD / NIST
Published: 2026-05-25T21:16:34.7+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 5.9/10EPSS 0.41%

Last modified Jun 17, 2026

CVE-2026-43827 is a medium-severity vulnerability rated 5.9/10 on the CVSS scale. Default configurations of Apache Shiro have a session fixation vulnerability. This issue affects Apache Shiro from 1.0 to 2.1.0, and 3.0.0-alpha-1. Users are recommended to upgrade to version 2.1.1, or 3.0.0-alpha-2 or later, which fixes the issue. In the affected versions, when a session already exists, it is not invalidated upon successful login, nor is a new session being generated with a new ID.. EPSS estimates a 0.41% chance of exploitation in the next 30 days.

Description

Default configurations of Apache Shiro have a session fixation vulnerability. This issue affects Apache Shiro from 1.0 to 2.1.0, and 3.0.0-alpha-1. Users are recommended to upgrade to version 2.1.1, or 3.0.0-alpha-2 or later, which fixes the issue. In the affected versions, when a session already exists, it is not invalidated upon successful login, nor is a new session being generated with a new ID.

Metrics

CVSS 3.1

6.5/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N

CVSS 4.0

5.9/10

CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:H/VI:N/VA:N/SC:L/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:Y/R:U/V:X/RE:L/U:Amber

EPSS Probability

0.41%

32.9th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-384

Affected Software

Vendor	Product	Versions	Update
Apache	Shiro	< 2.1.1	—
Apache	Shiro	3.0.0	Alpha1

References

https://shiro.apache.org/security-reports.html#cve_2026_43827Vendor Advisory
http://www.openwall.com/lists/oss-security/2026/05/25/6Mailing List, Third Party Advisory

Timeline

Published: May 25, 2026
Last Modified: Jun 17, 2026
Status: Analyzed

Frequently Asked Questions

What is CVE-2026-43827?

How severe is CVE-2026-43827?

CVE-2026-43827 has a CVSS score of 5.9/10 (MEDIUM severity). The EPSS model estimates a 0.41% probability of exploitation in the next 30 days.

How do I fix CVE-2026-43827?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2026-43827?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST