LDAP Injection in Apache Shiro

CVE-2026-49268

A remote attacker can inject LDAP special characters into the Distinguished Name (DN) construction in DefaultLdapRealm class. User-supplied username input is directly concatenated into the LDAP DN template without any escaping of RFC 2253 special characters. This allows an attacker to manipulate the DN structure used for LDAP bind authentication, potentially bypassing authentication or impersonating other users. This issue affects all Apache Shiro versions through 2.2.0, and 3.0.0-alpha-1 when using DefaultLdapRealm Upgrade to Apache Shiro 2.2.1 or 3.0.0-alpha-2 or later, which fixes the issue.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 9.1 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N.

EPSS exploit prediction

EPSS: 0.008 (53.3th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 53rd percentile — 53.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-49268: held from 0.005 to 0.008.

EPSS over last 30 days · oldest: 0.005 · newest: 0.008 · change: +0.003

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2026-49268?
CVE-2026-49268 is a critical-severity vulnerability in Apache Shiro, classified under LDAP Injection. CVSS score: 9.1/10. Published 2026-06-17.
How severe is CVE-2026-49268?
Critical severity. CVSS v3 base score is 9.1 out of 10.
Is CVE-2026-49268 known to be exploited?
2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.