CVE-2026-23901

Observable Timing Discrepancy vulnerability in Apache Shiro. This issue affects Apache Shiro: from 1.*, 2.* before 2.0.7. Users are recommended to upgrade to version 2.0.7 or later, which fixes the issue. Prior to Shiro 2.0.7, code paths for non-existent vs. existing users are different enough, that a brute-force attack may be able to tell, by timing the requests only, determine if the request failed because of a non-existent user vs. wrong password. The most likely attack vector is a local attack only. Shiro security model https://shiro.apache.org/security-model.html#username_enumeration discusses this as well. Typically, brute force attack can be mitigated at the infrastructure level.

CVSS v3 2.5 LOW

2.5^/10

CVSS v3 : LOW

Vector :

Exploitability : 1.0 / Impact : 1.4

Attack Vector LOCAL

Attack Complexity HIGH

Privileges Required LOW

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://lists.apache.org/thread/mm1jct9b86jvnh3y44tj22xvjtx3xhhh	Issue Tracking Third Party Advisory Mailing List
http://www.openwall.com/lists/oss-security/2026/02/08/2	Mailing List Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:apache:shiro:*:*:*:*:*:*:*:*

History

12 Feb 2026, 15:30

Type	Values Removed	Values Added
References	~~() https://lists.apache.org/thread/mm1jct9b86jvnh3y44tj22xvjtx3xhhh -~~	() https://lists.apache.org/thread/mm1jct9b86jvnh3y44tj22xvjtx3xhhh - Issue Tracking, Third Party Advisory, Mailing List
References	~~() http://www.openwall.com/lists/oss-security/2026/02/08/2 -~~	() http://www.openwall.com/lists/oss-security/2026/02/08/2 - Mailing List, Third Party Advisory
First Time		Apache shiro Apache
CPE		cpe:2.3:a:apache:shiro::::::::
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 2.5

10 Feb 2026, 11:16

Type	Values Removed	Values Added
References		() http://www.openwall.com/lists/oss-security/2026/02/08/2 -

10 Feb 2026, 10:15

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-02-10 10:15

Updated : 2026-02-12 15:30

NVD link : CVE-2026-23901

Mitre link : CVE-2026-23901

CVE.ORG link : CVE-2026-23901

JSON object : View

Products Affected

apache

shiro

CWE

CWE-208

Observable Timing Discrepancy

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