CVE•Published 2026-09-16•Modified 2026-09-18•0 articles on news•5 live references•NVD data

CVE-2026-59969Apache · Zookeeper

Vulnerability data via NVD (ingested)

CVSS v3.1

7.5

HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

EPSS percentile

Exploit Prediction Scoring System · top 97% of all CVEs

Weaknesses (CWE)

CWE-297Improper Validation of Certificate with Host Mismatch

Description

Apache ZooKeeper quorum TLS fails to enforce peer hostname verification in FIPS-mode deployments. When sslQuorum=true, zookeeper.fips-mode=true, ssl.quorum.hostnameVerification=true, and ssl.quorum.clientHostnameVerification=true are enabled, the Java SSLSocket quorum path accepts a CA-trusted peer certificate whose SAN does not match the connected host. A malicious or misissued peer certificate can therefore join quorum traffic, participate in leader election, and enter replication flows. Users are recommended to upgrade to version 3.8.7 or 3.9.6, which fixes the issue.

Timeline

Published 2026-09-16

Modified 2026-09-18

External references

NVD MITRE Exploit-DB GitHub PoC VulnCheck

Search for exposed instances

Shodan + Censys queries derived from NVD's CPE data. The vuln tag catches assets Shodan has explicitly linked to this CVE; the product / banner fingerprints find exposed instances even when the vuln tag was never applied (which is common).

Shodan · vuln tag0 hosts

vuln:CVE-2026-59969

Hosts Shodan has explicitly fingerprinted as vulnerable.

Shodan · product

product:"Apache Zookeeper"

All exposed Apache Zookeeper instances — cross-reference with the CVE's affected-version range.

Shodan · banner/body mention

http.html:"Zookeeper"

HTTP body or banner mentions "Zookeeper" — catches deploys Shodan didn't identify as a product.

More intel sources (5)

Shodan report

vuln:CVE-2026-59969