Security Digest · Vulnerability record
CVE-2026-23906: Apache Druid Vulnerable to Authentication Bypass
Affected Products and Versions Apache Druid Affected Versions: 0.17.0 through 35.x (all versions prior to 36.0.0) Prerequisites: druid-basic-security extension enabled LDAP authenticator configured Underlying LDAP server permits anonymous bind Vulnerability Description An authentication bypass vulnerability exists in…
CVSS 9.3 Critical EPSS 1.1% · p66
Should you act?
Critical and remotely reachable
No known exploitation yet, but it is network-reachable without credentials. This signal is computed from CISA KEV, EPSS and CVSS data; it is not an editorial verdict.
- No confirmed exploitation. It is not in CISA’s KEV catalog and CISA’s SSVC assessment records no known exploitation. That can change quickly after a public write-up; re-check if you are affected.
- EPSS 1.1%, percentile 66: FIRST’s model estimates a 1.1% chance of exploitation activity in the next 30 days, higher than 66% of all scored CVEs (moderate). EPSS is a probability, not a verdict.
- Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
- Only applies if your dependency tree includes
org.apache.druid.extensions:druid-basic-security(Maven) >= 0.17.0, < 36.0.0, fixed in 36.0.0. Check your lockfile, including transitive dependencies.
What it is
Affected Products and Versions Apache Druid Affected Versions: 0.17.0 through 35.x (all versions prior to 36.0.0) Prerequisites: druid-basic-security extension enabled LDAP authenticator configured Underlying LDAP server permits anonymous bind Vulnerability Description An authentication bypass vulnerability exists in Apache Druid when using the druid-basic-security extension with LDAP authentication. If the underlying LDAP server is configured to allow anonymous binds, an attacker can bypass authentication by providing an existing username with an empty password. This allows unauthorized access to otherwise restricted Druid resources without valid credentials. The vulnerability stems from improper validation of LDAP authentication responses when anonymous binds are permitted, effectively treating anonymous bind success as valid user authentication. Impact A remote, unauthenticated attacker can: Gain unauthorized access to the Apache Druid cluster Access sensitive data stored in Druid datasources Execute queries and potentially manipulate data Access administrative interfaces if the bypassed account has elevated privileges Completely compromise the confidentiality, integrity, and availability of the Druid deployment Mitigation Immediate Mitigation (No Druid Upgrade Required): Disable anonymous bind on your LDAP server. This prevents the vulnerability from being exploitable and is the recommended immediate action. Resolution Upgrade Apache Druid to version 36.0.0 or later, which includes fixes to properly reject anonymous LDAP bind attempts.
From the GitHub advisory
Affected Products and Versions Apache Druid Affected Versions: 0.17.0 through 35.x (all versions prior to 36.0.0) Prerequisites: druid-basic-security extension enabled LDAP authenticator configured Underlying LDAP server permits anonymous bind
Vulnerability Description
An authentication bypass vulnerability exists in Apache Druid when using the druid-basic-security extension with LDAP authentication. If the underlying LDAP server is configured to allow anonymous binds, an attacker can bypass authentication by providing an existing username with an empty password. This allows unauthorized access to otherwise restricted Druid resources without valid credentials.
The vulnerability stems from improper validation of LDAP authentication responses when anonymous binds are permitted, effectively treating anonymous bind success as valid user authentication.
Impact
Weakness type: CWE-287.
Product: org.apache.druid.extensions:druid-basic-security (Maven) · Assigned by: apache · Published: 2026-02-10
Affected and fixed versions
| Ecosystem | Package | Vulnerable | First fixed |
|---|---|---|---|
| Maven | org.apache.druid.extensions:druid-basic-security | >= 0.17.0, < 36.0.0 | 36.0.0 |
| Vendor | Product | Affected versions (per CVE record) |
|---|---|---|
| Apache Software Foundation | Apache Druid | 0.17.0 < 36.0.0 |
Severity scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| CISA-ADP | 3.1 | 9.8 Critical | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| GitHub | 4.0 | 9.3 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N |
- Attack vector: network (remotely reachable)
- Attack complexity: low
- Attack requirements: none
- Privileges required: none (no login)
- User interaction: none
CVSS measures how bad a flaw is if exploited, not how likely exploitation is. Read it next to the exploitation data below.
Exploitation and urgency
- CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
- CISA SSVC assessment: exploitation none, automatable yes, technical impact total.
- FIRST EPSS (model of 2026-10-21): 1.13% probability of exploitation activity in the next 30 days; percentile 66.
Timeline
- — CVE record published by apache
- — GitHub-reviewed advisory GHSA-q672-hfc7-g833 published (critical)
- — CVE record last updated
Sources and references
Original sources first. Version and fix details should always be confirmed against the vendor or project advisory.
Vendor and project advisories, patches
- lists.apache.org lists.apache.org
Vulnerability records
- GitHub Advisory GHSA-q672-hfc7-g833 github.com
- CVE.org record CVE-2026-23906 cve.org
- NVD entry CVE-2026-23906 nvd.nist.gov
Other references from the CVE record and advisory
- openwall.com openwall.com