Apache ZooKeeper: Insertion of Sensitive Information into Log File (CVE-2026-24308)
Published
What is affected, what to do
Improper handling of configuration values in ZKConfig in Apache ZooKeeper 3.8.5 and 3.9.4 on all platforms allows an attacker to expose sensitive information stored in client configuration in the client's logfile. Configuration values are exposed at INFO level logging rendering potential production systems affected by the issue.
Update netty-codec-http to version 4.1.133.Final, netty-codec-http2 to version 4.1.133.Final, netty to version 4.1.133.Final.
- Affected
- Apache ZooKeeper
lte 3.9.0..3.9.4 - Apache ZooKeeper
lte 3.8.0..3.8.5
- Apache ZooKeeper
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Metrics
7.5
Priority
XIEM Effective CVSS: highest available CVSS rating from NVD and vendor data.
Source: NVD, CVSS v3
7.5
CVSS v3
Severity High on the scale from 0 to 10.
1.2 %
EPSS score
Moderate — model estimates 1-10% exploitation likelihood.
Source: FIRST EPSS, percentile 67.7
Show all metrics
- Severity
- High
Priority (0–325)
The priority score is a consolidated metric that condenses several individual signals into a single, action-guiding ranking: technical severity (CVSS), exploitation likelihood (EPSS), known-exploited status (KEV) and the context of the affected asset. The aim is to answer the only truly important question in vulnerability management: what first?
Read in glossary- 61.33 Methodology
Exploit maturity
An exploit is code or a technique that specifically uses a concrete vulnerability to force unintended behaviour — such as executing code or escalating privileges. It is the tool that turns a theoretical flaw into a practical attack.
Read in glossary- no public PoC known
XIEM Effective CVSS
XIEM® is the tiered managed-security operating model from NEOSEC and a registered trademark of NEOSEC GmbH. It extends classic SIEM — the central collection, normalisation and correlation of security-relevant events — with endpoint forensics, network visibility and deception technology, and consolidates them into three building tiers: Sentry, Orchestrate and Command.
Read in glossary- 7.5 Methodology
CVSS v3
CVSS is the globally established, open standard for assessing the technical severity of a vulnerability on a scale from 0 to 10. It describes how easily a flaw can be exploited and what damage it can cause — but not how likely its actual exploitation is. CVSS and the complementary EPSS deliberately answer different questions.
Read in glossary- 7.5
EPSS score
The EPSS score is the absolute model output for an individual vulnerability: the estimated probability of real-world exploitation within the next 30 days, expressed as a value between 0 and 1 (i.e. 0 % to 100 %). A score of 0.42 means „the model estimates a 42 % chance of real-world exploitation within 30 days“.
Read in glossary- 1.2 %
- Moderate — model estimates 1-10% exploitation likelihood.
EPSS percentile
The EPSS percentile is the relative position of a vulnerability within all EPSS-scored CVEs, expressed as a value between 0 and 1. A percentile of 0.90 means „this CVE has a higher EPSS score than 90 % of all other scored CVEs“. Unlike the EPSS score, it is not a probability — but a positioning within a ranking.
Read in glossary- 67.7
- High — this CVE ranks above the median of all CVEs scored today (rank ≥ 36%).
KEV status
The KEV catalogue is a list maintained by the US authority CISA of vulnerabilities for which active exploitation in the wild has been confirmed. It answers not the question „how severe?“ but „is it already being attacked?“ — thereby sharply prioritising patching.
Read in glossary- —
- Published
CWE
CWE is a catalogue of typical weakness types in software and hardware — such as flawed input validation, unsafe memory handling or poor authentication. Where a CVE names a concrete vulnerability in a concrete product, a CWE describes the underlying class of defect.
Read in glossary- CWE-532
Detection rules
No NEOSEC detection rule is available for this vulnerability yet.
Classification under NIS2 and CRA
Rule-based classification from exploitation status and severity. It does not replace a case-by-case assessment.
NIS2
NIS2 is EU Directive (EU) 2022/2555 to raise the level of cybersecurity across the Union. It substantially broadens obligations compared with the first NIS directive: more sectors, mandatory risk management, staged reporting duties and personal accountability of senior management.
Read in glossary- High technical severity: assess and remediate the vulnerability in vulnerability handling under Art. 21(2)(e) NIS2 and document the decision.
CRA
The CRA is EU Regulation (EU) 2024/2847 setting horizontal cybersecurity requirements for „products with digital elements“ — from industrial controllers and software to connected consumer devices. For the first time manufacturers must ensure security across the entire product lifecycle, handle vulnerabilities and provide security updates.
Read in glossary- From 11.12.2027, Annex I Part II CRA requires manufacturers of affected products with digital elements to handle vulnerabilities without delay and provide security updates.
ISO/IEC 27001
ISO/IEC 27001 is the internationally leading standard for an information security management system (ISMS). It describes a risk-based, process-oriented framework to systematically plan, implement, review and improve information security.
Read in glossary- Control A.8.8, management of technical vulnerabilities: assess relevance to your systems, plan remediation and keep evidence.
Description
Improper handling of configuration values in ZKConfig in Apache ZooKeeper 3.8.5 and 3.9.4 on all platforms allows an attacker to expose sensitive information stored in client configuration in the client's logfile. Configuration values are exposed at INFO level logging rendering potential production systems affected by the issue. Users are recommended to upgrade to version 3.8.6 or 3.9.5 which fixes this issue.
Source: BSI WID Portal
Affected products
The following versions are affected. Older releases of the same product line are also vulnerable unless stated otherwise.
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Apache Software Foundation | Apache ZooKeeper |
|
|
| io.netty | netty-codec-http |
|
|
| io.netty | netty-codec-http2 |
|
|
| netty | netty |
|
|
| Oracle Corporation | TimesTen In-Memory Database |
|
|
| SHAY | perl |
|
|
| apache | zookeeper |
|
|
| oracle | timesten_in-memory_database |
|
|
| perl | perl |
|
|
| Oracle | Commerce |
|
|
| Oracle | Communications |
|
|
| Oracle | Construction and Engineering |
|
|
| Oracle | Financial Services Applications |
|
|
| Oracle | Fusion Middleware |
|
|
From bundled advisories, not CVE-specific (37)
Product list of a bundled advisory that does not state which product this CVE affects.
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Atlassian | Bamboo Data Center |
|
|
| Atlassian | Bamboo Data Center LTS |
|
|
| Atlassian | Bamboo LTS |
|
|
| Atlassian | Bitbucket Data Center |
|
|
| Atlassian | Bitbucket Data Center LTS |
|
|
| Atlassian | Bitbucket LTS |
|
|
| Atlassian | Confluence Data Center |
|
|
| Atlassian | Confluence Data Center LTS |
|
|
| Atlassian | Confluence LTS |
|
|
| Atlassian | Crucible |
|
|
| Atlassian | Fisheye |
|
|
| Atlassian | Jira Data Center |
|
|
| Atlassian | Jira Data Center LTS |
|
|
| Atlassian | Jira LTS |
|
|
| Atlassian | Jira Service Management Data Center and Server |
|
|
| Open Source | Keycloak |
|
|
| Open Source | Netty |
|
|
Weakness classes (CWE)
CWE-532Insertion of Sensitive Information into Log File
Base
The product writes sensitive information to a log file.
Entry at MITRE CWE-532
References & sources
- oracle.comOracle AdvisoryVendor advisory
- CVE.org (MITRE)CVERecord?id=CVE-2026-3381Vendor advisory, related, Vulnerability database, Third-party advisory
- lists.security.metacpan.orgcve-announce/msg/37638919Vendor advisory, Third-party advisory
- github.comPerl/perl5/commit/c75ae9cc164205e1b6d6dbd57bd2c65c8593fe94Patch, Patch
- metacpan.orgrelease/PMQS/Compress-Raw-Zlib-2.221/source/ChangesRelease notes, Release notes
- metacpan.orgrelease/SHAY/perl-5.40.4/changesRelease notes, Release notes
- metacpan.orgrelease/SHAY/perl-5.42.2/changesRelease notes, Release notes
- openwall.comlists/oss-security/2026/03/30/2Mailing list, Third-party advisory
- github.comnetty/netty/security/advisories/GHSA-f6hv-jmp6-3vwvweb, x_refsource_CONFIRM
- NVD (NIST)vuln/detail/CVE-2026-42587advisory
- github.comnetty/nettypackage
- access.redhat.comsecurity/cve/CVE-2026-42587Vulnerability database, x_refsource_REDHAT
- bugzilla.redhat.comRHBZ#2477220Issue tracking, x_refsource_REDHAT
- security.access.redhat.comdata/csaf/v2/vex/2026/cve-2026-42587.jsonx_sadp-csaf-vex
- access.redhat.comerrata/RHSA-2026:28010Vendor advisory, x_refsource_REDHAT
- access.redhat.comerrata/RHSA-2026:41951Vendor advisory, x_refsource_REDHAT
- access.redhat.comerrata/RHSA-2026:50085Vendor advisory, x_refsource_REDHAT
- access.redhat.comerrata/RHSA-2026:42644Vendor advisory, x_refsource_REDHAT
- access.redhat.comerrata/RHSA-2026:25123Vendor advisory, x_refsource_REDHAT
- access.redhat.comerrata/RHSA-2026:36820Vendor advisory, x_refsource_REDHAT
Reanalysis & status changes
Chronological NVD audit events for this CVE — reanalyses, CVSS updates, CPE diffs.
CVE Modified0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- Reference: after https://access.redhat.com/errata/RHSA-2026:34608
- Affected:
before Red Hat AMQ Broker 7.12.7, Red Hat AMQ Broker 7.13.5, Red Hat AMQ Broker 7.14.0 (+13)after Red Hat AMQ Broker 7.12.7, Red Hat AMQ Broker 7.13.5, Red Hat AMQ Broker 7.14.0 (+13)
Linked CVEs
| Severity | CVE | Title | CVSS | Exploitation |
|---|---|---|---|---|
| Medium | CVE-2026-60411 | Oracle TimesTen In-Memory Database: security vulnerability | 6.5 | — |
| Medium | CVE-2026-60410 | Oracle TimesTen In-Memory Database: Denial of Service | 4.3 | — |
| Medium | CVE-2026-60409 | Oracle TimesTen In-Memory Database: Denial of Service | 5.7 | — |
| Medium | CVE-2026-60408 | Oracle TimesTen In-Memory Database: security vulnerability | 4.3 | — |
| Medium | CVE-2026-60407 | Oracle TimesTen In-Memory Database: security vulnerability | 5.6 | — |
| Medium | CVE-2026-60406 | Oracle TimesTen In-Memory Database: security vulnerability | 6.7 | — |
| Low | CVE-2026-60405 | Oracle TimesTen In-Memory Database: security vulnerability | 3.8 | — |
| Medium | CVE-2026-60404 | Oracle TimesTen In-Memory Database: security vulnerability | 6.5 | — |
| Medium | CVE-2026-60403 | Oracle TimesTen In-Memory Database: security vulnerability | 6.5 | — |
| Critical | CVE-2026-60402 | Oracle TimesTen In-Memory Database: security vulnerability | 9.9 | — |
| Medium | CVE-2026-60401 | Oracle TimesTen In-Memory Database: security vulnerability | 6.5 | — |
| High | CVE-2026-42587 | Netty: Uncontrolled Resource Consumption | 7.5 | — |
| Critical | CVE-2026-4176 | SHAY Perl: Dependency on Vulnerable Third-Party Component | 9.8 | — |
| High | CVE-2026-24308 | Apache ZooKeeper: Sensitive information disclosure in client configuration handling | 7.5 | — |
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<a href="https://intel.neosec.eu/en/cve/CVE-2026-24308"><img src="https://intel.neosec.eu/badge/cve/CVE-2026-24308.svg?lang=en" alt="CVE-2026-24308 – NEOSEC Intel" height="20"></a>