LogstashApplication · Elastic
CVE-2026-33466
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedImproper Limitation of a Pathname to a Restricted Directory (CWE-22) in Logstash can lead to arbitrary file write and potentially remote code execution via Relative Path Traversal (CAPEC-139). The archive extraction utilities used by Logstash do not properly validate file paths within compressed archives. An attacker who can serve a specially crafted archive to Logstash through a compromised or attacker-controlled update endpoint can write arbitrary files to the host filesystem with the privileges of the Logstash process. In certain configurations where automatic pipeline reloading is enabled, this can be escalated to remote code execution.
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysis · high confidenceLogstash contains a path traversal vulnerability (CWE-22) in its archive extraction utilities that fail to validate file paths within compressed archives. An attacker serving a specially crafted archive through a compromised update endpoint can write arbitrary files to the host filesystem with Logstash process privileges, potentially achieving RCE when automatic pipeline reloading is enabled.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.
NVD · CPE data
LogstashApplication
>= 8.0.0, < 8.19.14>= 9.0.0, < 9.2.8>= 9.3.0, < 9.3.3CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Network
- Complexity
- Low
- Privileges
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.
dbcve checksWork through these to decide whether this CVE applies to you.
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Identify Logstash installation and versionRun 'bin/logstash --version' (Linux/macOS) or check the installed package details. On Windows, check the installed programs list or the Logstash service version.Affected if The installed version falls within >=8.0.0 and <8.19.14, OR >=9.0.0 and <9.2.8, OR >=9.3.0 and <9.3.3
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Verify if update endpoints are accessibleCheck Logstash network configuration files (logstash.yml or pipelines.yml) for any exposed HTTP endpoints related to updates or plugin management. Review firewall rules and network ACLs controlling access to Logstash ports.Affected if Update or plugin management endpoints are exposed to untrusted networks or the attacker has network access to these endpoints
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Check automatic pipeline reloading configurationInspect the logstash.yml file for 'pipeline.reload.automatic: true' or check pipeline definitions for reload settings. Also review 'pipeline.reload.interval' to understand reload frequency.Affected if Automatic pipeline reloading is enabled (pipeline.reload.automatic is true), which would allow written malicious configs to be loaded and executed
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Inspect file permissions on Logstash directoriesReview the file ownership and permissions on the Logstash installation directory, particularly the 'plugins' and 'data' subdirectories, to understand the impact of arbitrary file write capability.Affected if Logstash runs with elevated privileges or has write access to sensitive directories outside its intended workspace
You are affected if your Logstash version is one of the vulnerable versions listed AND update endpoints are accessible to an attacker who could supply malicious archives, especially if automatic pipeline reloading is enabled which would allow the arbitrary file write to lead to RCE.
Generated from the published advisory. Verify against your own configuration.
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
dbcve · scoped8.19.149.2.89.3.3
Restrict network access to update endpoints, validate and sanitize all extracted file paths, and consider disabling automatic pipeline reloading as a defense-in-depth measure while awaiting official patch.
Logstash 8.19.14 (for 8.x) or 9.3.3 (for 9.x)
- Identify the current Logstash version by checking the installed version or looking at the logs
- Determine which major version branch is in use (8.x or 9.x)
- For Logstash 8.x users: Upgrade to version 8.19.14 or later
- For Logstash 9.0.x - 9.2.x users: Upgrade to version 9.2.8 or later
- For Logstash 9.3.x users: Upgrade to version 9.3.3 or later
- After upgrade, verify the Logstash service starts successfully
- If using automatic pipeline reloading, ensure the configuration is still functioning correctly post-upgrade
- Review and validate any custom pipeline configurations to ensure compatibility
Generated from the published advisory — verify against the referenced sources before acting.
Fix this in Logstash
Scoped from the published advisory
- Consultation6.0 h
- Implementation12.0 h
- Testing10.0 h
- Review / QA4.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $8,928.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2026-33466 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2026-33466 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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- Version or environment caveats, and links to real fixes
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