CyberSecBulletin
CVE-2026-73644NVD status: Deferred

OpenDJ: Improper Authorization

CVE-2026-73644 is a critical-severity improper authorization vulnerability in OpenDJ from OpenIdentityPlatform, with a CVSS 3.1 base score of 9.6 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, without any action from a user. Affected OpenDJ versions: < 5.1.2. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.41% chance of exploitation within 30 days, which is low compared with other CVEs.

Patch this week

Critical severity: a successful attack would have severe impact.

What to do

  1. Check which version of OpenDJ you run against the affected versions below, and install the vendor's latest release.
  2. Read the advisory on github.com for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
OpenIdentityPlatformOpenDJ< 5.1.2Not stated

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
LowA basic user account is enough.
User interaction
NoneNo action by a victim is required.
Scope
ChangedThe attack can reach beyond the vulnerable component into other systems.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
NoneAvailability is not affected.

Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N. Scored by CNA (github.com).

Official description

OpenDJ is an LDAPv3 compliant directory service. Prior to 5.1.2, the SASL PLAIN authorization identity path in opendj-server-legacy/src/main/java/org/opends/server/extensions/PlainSASLMechanismHandler.java checked the PROXIED_AUTH privilege but did not evaluate the mayProxy proxy ACI scope when an authzid resolved to a different user. Both dn: and u: or bare authzid forms could therefore let an authenticated account holding PROXIED_AUTH assume any resolvable non-root identity outside the identities permitted by its proxy ACI. The fix returns INVALID_CREDENTIALS (49) before password verification when the target authorization identity is not permitted. This issue is fixed in version 5.1.2.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Improper Authorization

The product does not perform or incorrectly performs an authorization check when an actor attempts to access a resource or perform an action.

How developers prevent this class of flaw

  • Divide the product into anonymous, normal, privileged, and administrative areas. Reduce the attack surface by carefully mapping roles with data and functionality. Use role-based access control (RBAC) to enforce the roles at the appropriate boundaries. Note that this approach may not protect against horizontal authorization, i.e., it will not protect a user from attacking others with the same role.
  • Ensure that you perform access control checks related to your business logic. These checks may be different than the access control checks that you apply to more generic resources such as files, connections, processes, memory, and database records. For example, a database may restrict access for medical records to a specific database user, but each record might only be intended to be accessible to the patient and the patient's doctor.
  • Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. For example, consider using authorization frameworks such as the JAAS Authorization Framework and the OWASP ESAPI Access Control feature.

More Improper Authorization vulnerabilities (CWE-285)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in OpenDJ

All OpenDJ vulnerabilities

Recent Improper Authorization vulnerabilities

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