← Vulnerability feed

Vulnerability record · CVE-2026-23901 · published 10 February 2026

CVE-2026-23901: Apache shiro vulnerability

Apache · Shiro

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.

1.0 CVSS 4.0 Low EPSS 0.22% · top 88.4% CWE-208 · CWE-208
1.0CVSS 4.0 base score
0.22%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
2References
17 Jun 2026Last modified by NVD

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: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:

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://lists.apache.org/thread/mm1jct9b86jvnh3y44tj22xvjtx3xhhh Issue TrackingMailing ListThird Party Advisory
http://www.openwall.com/lists/oss-security/2026/02/08/2 Mailing ListThird Party Advisory

Track CVE-2026-23901 inside VULONE

Watch it alongside the ransomware crews, C2 infrastructure and forum chatter that reference it, query it through the API and pull it into your SIEM over TAXII.

Start free Open in platform

Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

9.8CVE-2016-4437Apache Shiro hardcoded remember-me cipher key enables code executionApache Shiro before 1.2.5 uses a default cipher key for the "remember me" feature when no key is configured, allowing attackers to forge or decrypt r…KEVEPSS 93%analysed9.8CVE-2023-34478Apache shiro path traversal vulnerabilityApache Shiro, before 1.12.0 or 2.0.0-alpha-3, may be susceptible to a path traversal attack that results in an authentication bypass when used togeth…EPSS 2.1%9.8CVE-2022-40664Apache shiro improper authentication vulnerabilityApache Shiro before 1.10.0, Authentication Bypass Vulnerability in Shiro when forwarding or including via RequestDispatcher.EPSS 2.7%9.8CVE-2022-32532Apache shiro incorrect authorization vulnerabilityApache Shiro before 1.9.1, A RegexRequestMatcher can be misconfigured to be bypassed on some servlet containers. Applications using RegExPatternMatch…EPSS 26%9.8CVE-2021-41303Apache Shiro with Spring Boot authentication bypass via crafted HTTP requestApache Shiro before 1.8.0, when used with Spring Boot, can be tricked by a specially crafted HTTP request into bypassing authentication. The flaw is …EPSS 77%analysed9.8CVE-2020-17523Apache Shiro with Spring authentication bypass via crafted HTTP requestApache Shiro before 1.7.1, when used with Spring, can be made to bypass authentication by a specially crafted HTTP request. The flaw is an improper a…EPSS 86%analysed9.8CVE-2020-17510Apache shiro improper authentication vulnerabilityApache Shiro before 1.7.0, when using Apache Shiro with Spring, a specially crafted HTTP request may cause an authentication bypass.EPSS 8.2%9.8CVE-2020-11989Apache shiro vulnerabilityApache Shiro before 1.5.3, when using Apache Shiro with Spring dynamic controllers, a specially crafted request may cause an authentication bypass.EPSS 24%

Source: NIST National Vulnerability Database (record CVE-2026-23901), CISA KEV, FIRST EPSS (scores of 2026-09-27). This page is refreshed as NVD updates the record.