CVE-2026-242815.9MediumCWE-350

CVE-2026-24281: Apache ZooKeeper: Reverse-DNS fallback enables hostname verification bypass in ZooKeeper ZKTrustManager

Apache Software Foundation · Apache ZooKeeper

Vendor fix available · Affected: Apache Software Foundation Apache ZooKeeper · Exploitation: unlikely (under 1%)

Not in CyberSIXT coverage yet: no article names this CVE. This page shows the public record.

0.7%probability of exploitation in the next 30 days

53rd percentile

050100

Higher than 53% of scored CVEs

5.9MediumCVSS 3.1

LowMediumHighCrit.

DescriptionCVE.org

Hostname verification in Apache ZooKeeper ZKTrustManager falls back to reverse DNS (PTR) when IP SAN validation fails, allowing attackers who control or spoof PTR records to impersonate ZooKeeper servers or clients with a valid certificate for the PTR name. It's important to note that attacker must present a certificate which is trusted by ZKTrustManager which makes the attack vector harder to exploit. Users are recommended to upgrade to version 3.8.6 or 3.9.5, which fixes this issue by introducing a new configuration option to disable reverse DNS lookup in client and quorum protocols.

Affected products1

From the CVE record. A product or version that is not listed is unknown, not unaffected.

Apache Software Foundation · Apache ZooKeeperfrom 3.9.0 up to and including 3.9.4; from 3.8.0 up to and including 3.8.5

On the Atlas

Every published CVE is on the CyberSIXT Atlas, grouped by weakness, vendor and month.

Open the Atlas

Exploitation: Unlikely (under 1%). EPSS under 1%, or no score yet.
CISA KEV: Not listed
Public check: No public nuclei template
Weakness: Reliance on Reverse DNS Resolution for a Security-Critical Action · Authentication
Vendor: Apache Software Foundation
Published: March 2026
Band: Unlikely (under 1%), March 2026

CoverageNo articles yet

No CyberSIXT article names CVE-2026-24281 yet, so there is no coverage timeline, action brief or change log for it. Everything on this page comes from the public CVE record, CISA KEV, EPSS and the nuclei template index. Search the archive or see the CVEs in the news.