GHSA-P279-2CQP-84JG
Vulnerability from github – Published: 2026-07-24 21:46 – Updated: 2026-08-13 17:52Summary
When a SASL PLAIN bind supplies an authorization identity (authzid) that resolves to a different user, PlainSASLMechanismHandler verified only the PROXIED_AUTH privilege and never evaluated the "proxy" access-control right (the mayProxy ACI scope check). As a result, any account holding the proxied-auth privilege could assume any resolvable non-root identity without being granted a proxy ACI for that target.
This diverges from every other proxy path in OpenDJ — the proxied-authorization controls (RFC 4370) and the DIGEST-MD5 / GSSAPI authzid handlers all require both the privilege and the mayProxy scope grant.
Impact
Privilege escalation / authorization bypass: a holder of proxied-auth can act as arbitrary directory users beyond the scope intended by the deployment's proxy ACIs, defeating the ACI-based restriction on which identities may be impersonated. Root/Directory Manager is not assumable this way.
Fix
Enforce the mayProxy scope check on the SASL PLAIN authzid path (both dn: and u:/bare forms), sharing one hasProxyAccess helper with the DIGEST-MD5/GSSAPI path. Denial returns INVALID_CREDENTIALS (49) before password verification — matching DIGEST-MD5/GSSAPI — so an unauthenticated client cannot distinguish a missing privilege from a missing ACI grant.
Workaround
Restrict or revoke the proxied-auth privilege until upgraded.
{
"affected": [
{
"database_specific": {
"last_known_affected_version_range": "\u003c= 5.1.1"
},
"package": {
"ecosystem": "Maven",
"name": "org.openidentityplatform.opendj:opendj-server-legacy"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "5.1.2"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2026-73644"
],
"database_specific": {
"cwe_ids": [
"CWE-285",
"CWE-639"
],
"github_reviewed": true,
"github_reviewed_at": "2026-07-24T21:46:39Z",
"nvd_published_at": null,
"severity": "CRITICAL"
},
"details": "### Summary\nWhen a SASL PLAIN bind supplies an authorization identity (authzid) that resolves to a **different** user, PlainSASLMechanismHandler verified only the PROXIED_AUTH privilege and never evaluated the \"proxy\" access-control right (the mayProxy ACI scope check). As a result, any account holding the proxied-auth privilege could assume **any resolvable non-root identity** without being granted a proxy ACI for that target.\n\nThis diverges from every other proxy path in OpenDJ \u2014 the proxied-authorization controls (RFC 4370) and the DIGEST-MD5 / GSSAPI authzid handlers all require **both** the privilege **and** the mayProxy scope grant.\n\n### Impact\nPrivilege escalation / authorization bypass: a holder of proxied-auth can act as arbitrary directory users beyond the scope intended by the deployment\u0027s proxy ACIs, defeating the ACI-based restriction on *which* identities may be impersonated. Root/Directory Manager is not assumable this way.\n\n### Fix\nEnforce the mayProxy scope check on the SASL PLAIN authzid path (both dn: and u:/bare forms), sharing one hasProxyAccess helper with the DIGEST-MD5/GSSAPI path. Denial returns INVALID_CREDENTIALS (49) **before** password verification \u2014 matching DIGEST-MD5/GSSAPI \u2014 so an unauthenticated client cannot distinguish a missing privilege from a missing ACI grant.\n\n### Workaround\nRestrict or revoke the proxied-auth privilege until upgraded.",
"id": "GHSA-p279-2cqp-84jg",
"modified": "2026-08-13T17:52:54Z",
"published": "2026-07-24T21:46:39Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/OpenIdentityPlatform/OpenDJ/security/advisories/GHSA-p279-2cqp-84jg"
},
{
"type": "WEB",
"url": "https://github.com/OpenIdentityPlatform/OpenDJ/commit/5c326850f1ab945cfca7ac9c5aaf77d1052c6bed"
},
{
"type": "PACKAGE",
"url": "https://github.com/OpenIdentityPlatform/OpenDJ"
},
{
"type": "WEB",
"url": "https://github.com/OpenIdentityPlatform/OpenDJ/releases/tag/5.1.2"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N",
"type": "CVSS_V3"
}
],
"summary": "OpenDJ SASL PLAIN authzid bypassing the proxy ACI scope check"
}
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.