cbcvebase.
CVE-2026-24281
published 2026-03-07

CVE-2026-24281: Hostname verification in Apache ZooKeeper ZKTrustManager falls back to reverse DNS (PTR) when IP SAN validation fails, allowing attackers who control or spoof…

PriorityP350high7.4CVSS 3.1
AVNACHPRNUINSUCHIHAN
EPSS
0.63%
46.3th percentile
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

6 ranges
VendorProductVersion rangeFixed in
apachezookeeper>= 0 < 3.9.5-13.9.5-1
apachezookeeper>= 3.8.0 < 3.8.63.8.6
apachezookeeper>= 3.9.0 < 3.9.53.9.5
apache_software_foundationapache_zookeeper3.8.0 – 3.8.5
apache_software_foundationapache_zookeeper3.9.0 – 3.9.4
debianzookeeper< zookeeper 3.9.5-1 (forky)zookeeper 3.9.5-1 (forky)

CVSS provenance

nvdv3.17.4HIGHCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
osv7.4HIGH
vendor_debian7.4HIGH
vendor_redhat7.4HIGH
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