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CVE-2026-49268 Apache CVE debrief

CVE-2026-49268 is a high-severity vulnerability in Apache Shiro that allows remote attackers to inject LDAP special characters, potentially bypassing authentication or impersonating users. The issue affects all Apache Shiro versions up to 2.2.0 and 3.0.0-alpha-1 when using DefaultLdapRealm. Attackers can exploit this by directly concatenating user-supplied username input into the LDAP DN template without proper escaping of RFC 2253 special characters. To mitigate, upgrade to Apache Shiro 2.2.1 or 3.0.0-alpha-2 or later. This fix addresses the LDAP injection vulnerability, preventing attackers from manipulating the DN structure used for LDAP bind authentication.

Vendor
Apache
Product
Shiro
CVSS
HIGH 8.8
CISA KEV
Not listed in stored evidence
Original CVE published
2026-06-17
Original CVE updated
2026-06-18
Advisory published
2026-06-17
Advisory updated
2026-06-18

Who should care

Security teams and administrators responsible for Apache Shiro deployments should prioritize patching this high-severity vulnerability. Developers using Shiro for authentication and authorization should assess their exposure and upgrade to a patched version. Organizations relying on Shiro for access control should treat this as a critical update.

Technical summary

The CVE-2026-49268 vulnerability in Apache Shiro arises from the insecure construction of LDAP Distinguished Names (DNs) in the DefaultLdapRealm class. User-supplied input is directly concatenated into the LDAP DN template without proper escaping of special characters defined in RFC 2253. This allows attackers to inject LDAP special characters, potentially bypassing authentication mechanisms or impersonating other users. The vulnerability affects all versions of Apache Shiro up to 2.2.0 and 3.0.0-alpha-1 when using DefaultLdapRealm. The fix involves upgrading to Apache Shiro 2.2.1 or 3.0.0-alpha-2 or later, which properly escapes special characters in LDAP DNs.

Defensive priority

High

Recommended defensive actions

  • Upgrade to Apache Shiro 2.2.1 or 3.0.0-alpha-2 or later
  • Review and update authentication configurations for DefaultLdapRealm
  • Implement additional monitoring for suspicious LDAP activity
  • Ensure proper input validation and sanitization for user-supplied data
  • Consider using alternative authentication mechanisms temporarily if upgrade is not feasible
  • Apply security patches and updates regularly for Apache Shiro

Evidence notes

The CVE-2026-49268 vulnerability is confirmed through official Apache Shiro documentation and NVD records. The issue is accurately described in the CVE record and vendor advisories. The fix is verified through Apache Shiro release notes for versions 2.2.1 and 3.0.0-alpha-2.

Official resources

public