CVE-2026-23901
lowpriority · track · 10EPSS 0.002 · 16 %ileEUFRUSEPSS · scored 2026-10-27
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
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (3)
Products and version ranges known to be affected.
advisories (2)
Vendor and ecosystem advisories describing this.
- GHSA-c4qc-4q9p-m9q9Apache Shiro Affected by an Observable Timing Discrepancy Vulnerability2026-02-10ghsa · osvUS
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.
- CERTFR-2026-AVI-1385Multiples vulnérabilités dans les produits VMwareFrançais2026-10-26vendor · certfrFR
also known as (3)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (7)
External citations — patches, advisories, analysis.
- http://www.openwall.com/lists/oss-security/2026/02/08/2cnnvd
- https://access.redhat.com/security/cve/cve-2026-23901cnnvd
- https://lists.apache.org/thread/mm1jct9b86jvnh3y44tj22xvjtx3xhhhcnnvd
- https://shiro.apache.org/download.htmlPatchcnnvd
- https://lists.apache.org/thread/mm1jct9b86jvnh3y44tj22xvjtx3xhhhenisa_euvd
- http://www.openwall.com/lists/oss-security/2026/02/08/2Mailing ListThird Party Advisorynvd
- https://lists.apache.org/thread/mm1jct9b86jvnh3y44tj22xvjtx3xhhhIssue TrackingMailing ListThird Party Advisorynvd
Attackers weaponise vulnerabilities like this against internet-exposed services. See what is exposed on your perimeter with a free passive scan.
Free scan