7.4

CVE-2026-24281: apache software foundation apache zookeeper Improper Certificate Validation

CVSS: 7.4v3.1HighModified
AliasesUBUNTU-CVE-2026-24281DEBIAN-CVE-2026-24281CGA-2264-3cg6-c577
Published 07-03-2026Last modified 15-07-2026
Open JSON

Vulnerability summary

CVE-2026-24281 is a high (CVSS 7.4) Improper Certificate Validation vulnerability in apache software foundation apache zookeeper. EPSS estimates a 0.65% chance of exploitation in the next 30 days, higher than 49.8% of scored vulnerabilities.

Overall risk
30/100
0100
Medium · default modelHow is this calculated?
CVSS score
7.4/10
010
High · v3.1 (NVD)
EPSS score
0.65%
0%100%
Low · +0.01 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 0 · Related 1
CGA-5J23-P9GQ-43R4

Timeline

  1. 07-03-2026
    PublishedVulnerability first disclosed.
  2. 15-07-2026
    Last modifiedVulnerability information updated.

Description

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.

CVSS metrics

7 scores · 7 sources · 1 version

EPSS trend

Probability

0.65%

Chance of exploitation in the next 30 days

Percentile

50%

Versus all other CVEs

30-day change

+0.01 pp

From 0.63% on 18-09-2026

18-09-202618-10-2026
EPSS score
0.65%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Chainguard40 products
  • akhq< 0.26.0-r11
  • apache-activemq-artemis< 2.53.0-r2
  • apache-nifi< 2.8.0-r4
  • apache-pulsar-4.1< 4.1.3-r7
  • apache-pulsar-fips-4.1< 4.1.3-r7
Wolfi27 products
  • akhq< 0.26.0-r11
  • apache-activemq-artemis< 2.53.0-r2
  • apache-nifi< 2.8.0-r4
  • apache-pulsar-4.1< 4.1.3-r7
  • confluent-common-dockerAll versions (No fix recorded)
Apache1 product
  • zookeeper≥ 3.8.0, < 3.8.6 | ≥ 3.9.0, < 3.9.5
Apache software foundation1 product
Debian1 product
  • zookeeperAll versions (No fix recorded) | < 3.9.5-1
Org.apache.zookeeper1 product
  • zookeeper≥ 3.8.0, < 3.8.6 | ≥ 3.9.0, < 3.9.5
Ubuntu1 product
  • zookeeperAll versions (No fix recorded)

7 vendors · 72 products

References

19 links
Show all 19 references