01/Description
What this actually is.
Technical background, root cause, and affected surface.
Apache Airflow FAB Auth Manager contains an LDAP filter injection vulnerability (CWE-90) that allows unauthenticated attackers to exfiltrate directory data or bypass authentication. Upgrade to apache-airflow-providers-fab 3.6.4 or later. If immediate upgrade is not possible, disable LDAP authentication until the provider can be updated.
- Vendor
- Apache Software Foundation
- Product
- Apache Airflow FAB provider
- Severity
- Medium
- CVSS Score
- 5.3
- Status
- Published
- CWE
- CWE-90: Improper Neutralization of Special Elements used in an LDAP Query ('LDAP Injection')
- Vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
02/Proof of ConceptFrom one request
From one request
to root shell.
Reproduced in a sandboxed environment. Requires only LAN or WiFi adjacency.
PoC · Exploitation Steps▲ trigger
01No Evidences
03/Vulnerable Code
The bug, and the fix.
No Evidences
04/Impact
What an attacker does to you.
Post-exploitation outcomes mapped to CVSS impact metrics.
Medium
The Apache Airflow FAB Auth Manager contains an LDAP filter injection vulnerability (CWE-90, Improper Neutralization of Special Elements used in an LDAP Query). Per the title recorded on this entry, the defect is in _search_ldap and is reachable from the /auth/token login endpoint.
Medium
Consequence as stated by the vendor: unauthenticated attackers can exfiltrate directory data or bypass authentication.
High
Attacker position: unauthenticated and remote. The recorded CVSS:3.1 vector is AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N (5.3) - network reach, low attack complexity, no privileges, no user interaction, low confidentiality impact only.
High
Note the tension between the two, flagged rather than resolved: "bypass authentication" and directory-data exfiltration would normally imply integrity impact and higher confidentiality impact than the recorded vector's C:L/I:N/A:N expresses. The vector as scored describes bounded information disclosure; the narrative describes an authentication bypass. Confirm which is intended before publication, since the two support materially different risk ratings. No evidence in the reviewed set independently establishes either outcome.
Medium
Why the endpoint matters: reachability from /auth/token means the injection is exercised during login, before any credential is validated, which is what makes the path pre-authentication. Injected filter syntax is evaluated by the directory server rather than by Airflow, so the blast radius is defined by what the bind account can enumerate in the directory, not by the permissions of any Airflow role.
High
Affected versions per the record: apache-airflow-providers-fab before 3.6.4.
High
Scope note: this is the vendor-stated impact. No local reproduction artifacts, PoC, or captured output exist for this CVE in the reviewed evidence set, and no exploitation was performed or verified by Securin.
05/Remediation
Fix it. In this order.
A runbook, not a checklist. Sequence matters — assume compromise before you act.
01
Upgrade to apache-airflow-providers-fab 3.6.4 or later.
N/A
02
Vendor-stated interim mitigation: if immediate upgrade is not possible, disable LDAP authentication until the provider can be updated. This is effective because the injection sink is _search_ldap, reached on the LDAP login path - with LDAP authentication disabled, that path is not exercised.
≤ 24 HR
03
Scoping: this is a provider-package issue, not an Airflow core issue. Check the installed apache-airflow-providers-fab version specifically - an up-to-date apache-airflow core install does not imply a patched FAB provider, since providers are versioned and upgraded independently. Affected range recorded on this entry: before 3.6.4.
N/A
04
Additional containment where LDAP authentication cannot be disabled and the upgrade is not yet deployed:
N/A
05
Restrict network access to the Airflow web/API tier, since the defect is reachable pre-authentication from the /auth/token login endpoint and therefore cannot be gated by Airflow roles or permissions.
N/A
06
Constrain the directory bind account used by the FAB LDAP integration to the minimum search scope and attribute set it needs. The injected filter is evaluated with that account's privileges, so narrowing it directly bounds what an injection can enumerate.
N/A
07
Enable and review directory-server query logging for anomalous or malformed filter syntax originating from the Airflow bind account, which is the observable signal of this being exercised.
N/A
08
These reduce reachability and blast radius; only the provider upgrade removes the injection.
N/A
Securin advisory — For coordinated remediation support or threat-actor briefings related to CVE-2026-46745, contact
disclose@securin.io06/Disclosure TimelineVendors moved in days.
Vendors moved in days.
Attackers in hours.
Reconstructed from vendor advisories, CISA bulletins, and Securin research records.
2026-05-25
Recorded in the Securin Zero-Days DB as published_date for CVE-2026-46745 (affected versions recorded as apache-airflow-providers-fab <3.6.4 · CVE status at time of entry: Published · advisory_status: Published)
2026-05-25
Vendor advisory records apache-airflow-providers-fab 3.6.4 as the fixed version, with disabling LDAP authentication as the interim mitigation
Disclosed 0 days after discovery
07/References
Cite, verify, go deeper.
Primary sources — NVD, CISA KEV, and machine-readable IoC feed.
NVD
NVD — CVE-2026-46745
nvd.nist.gov/vuln/detail/CVE-2026-46745 →SEC