JenkinsApplication
CVE-2021-21602
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 · uneditedJenkins 2.274 and earlier, LTS 2.263.1 and earlier allows reading arbitrary files using the file browser for workspaces and archived artifacts by following symlinks.
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 confidenceJenkins versions 2.274 and earlier, and LTS 2.263.1 and earlier contain a path traversal vulnerability in the file browser for workspaces and archived artifacts. The file browser follows symbolic links, allowing authenticated users with file access permissions to read arbitrary files on the Jenkins controller filesystem by creating or referencing symlinks.
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
JenkinsApplication
<= 2.263.1<= 2.274CVSS 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
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- None
- Availability
- None
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
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 installed Jenkins versionNavigate to Manage Jenkins > About Jenkins, or run: java -jar jenkins.war --version, or check the version file in the Jenkins home directoryAffected if The installed version is 2.274 or earlier, or LTS 2.263.1 or earlier
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Verify file browser access is enabledGo to Manage Jenkins > Configure Global Security and check the Authorization settings. Look for permissions granting File access or workspace/artifact browsing to authenticated usersAffected if Any authenticated user (including users with limited permissions) can access the file browser for workspaces or archived artifacts
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Check for symlinks in workspace directoriesInspect the directory configured for Jenkins workspaces (typically $JENKINS_HOME/workspace). Run: ls -la <workspace_path> to list all files and symbolic links. Also check archived artifact directories in $JENKINS_HOME/jobs/<jobname>/archiveAffected if Symbolic links exist in workspace or archived artifact directories pointing outside the expected directory tree
You are affected if your Jenkins version is 2.274 or earlier (or LTS 2.263.1 or earlier) AND authenticated users have file access permissions to browse workspaces or archived artifacts.
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.
From vendor dataUpgrade Jenkins to version 2.274.1 or LTS 2.263.2 or later. These versions include fixes that prevent the file browser from following symlinks outside the expected directory tree.
Fix this in Jenkins
Scoped from the published advisory
- Consultation1.0 h
- Implementation2.0 h
- Testing2.0 h
- Review / QA1.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $1,664.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2021-21602 — 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-2021-21602 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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A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.
- Verified mitigations, workarounds, and config changes
- Version or environment caveats, and links to real fixes
- No weaponised exploit code, or anything meant to cause harm
- No spam, self-promotion, credentials, or personal data