VulnerabilityDeferred

CVE-2026-56091

When using Apache Shiro with the shiro-guice module in a web servlet context, a specially crafted HTTP request may cause an authentication bypass.

HIGH 8.2EPSS 0.67%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.67%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

When using Apache Shiro with the shiro-guice module in a web servlet context, a specially crafted HTTP request may cause an authentication bypass. This vulnerability is similar to https://www.cve.org/CVERecord?id=CVE-2020-1957 https://www.cve.org/CVERecord , except that it affects the `shiro-guice` module instead of the `shiro-spring` module. This issue affects all Apache Shiro versions through 2.x, and 3.0.0-alpha-1 only when using `shiro-guice` module in a web servlet context. Upgrade to version 3.0.0 or later, which fixes the issue.

CVSS 4.0: 8.2 HIGHCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
EPSS: 0.67% probability · 50th percentile
CISA KEV: Not listed
Weakness: CWE-289
Source: security@apache.org

References

https://lists.apache.org/thread/onmtxmy2qonbpx7xlw3o34x8sctv47r7

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.