cbcvebase.
CVE-2026-23901
published 2026-02-10

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…

PriorityP410low2.5CVSS 3.1
AVLACHPRLUINSUCLINAN
EPSS
0.22%
12.3th percentile
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.

Affected

3 ranges
VendorProductVersion rangeFixed in
apacheshiro< 2.0.72.0.7
apache_software_foundationapache_shiro< 2.0.72.0.7
debianshiro

CVSS provenance

nvdv3.12.5LOWCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N
nvdv4.01.0LOWCVSS: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
osv1.0LOW
vendor_debian1.0LOW
vendor_redhat1.0LOW
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