CVE-2026-23901
Description
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 Details
CVSS:4.0/AV:L/AC:H/AT:P/PR:L/UI:A/VC:L/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:N/AU:Y/R:A/V:C/RE:L/U:Green Threat Intelligence
Weaknesses 1
Affected Products 1
| Vendor | Product | Version | Range |
|---|---|---|---|
| apache | shiro | * | <2.0.7 |
References 2
- openwall.com http://www.openwall.com/lists/oss-security/2026/02/08/2
- lists.apache.org https://lists.apache.org/thread/mm1jct9b86jvnh3y44tj22xvjtx3xhhh
Remediation
No remediation data recorded yet
Check vendor advisories and the NVD entry for patch availability.