Commons VfsApplication · Apache
CVE-2025-27553
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 · uneditedRelative Path Traversal vulnerability in Apache Commons VFS before 2.10.0. The FileObject API in Commons VFS has a 'resolveFile' method that takes a 'scope' parameter. Specifying 'NameScope.DESCENDENT' promises that "an exception is thrown if the resolved file is not a descendent of the base file". However, when the path contains encoded ".." characters (for example, "%2E%2E/bar.txt"), it might return file objects that are not a descendent of the base file, without throwing an exception. This issue affects Apache Commons VFS: before 2.10.0. Users are recommended to upgrade to version 2.10.0, which fixes the issue.
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 confidencePath traversal vulnerability in Apache Commons VFS where the resolveFile method with NameScope.DESCENDENT fails to properly validate URL-encoded path sequences (%2E%2E), allowing access to files outside the intended directory scope by bypassing the descendant validation.
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
Commons VfsApplication
< 2.10.0CVSS 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
- None
- Availability
- None
CVSS:3.1/AV:N/AC:L/PR:N/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 Apache Commons VFS version in useLocate the commons-vfs JAR file in your classpath or build dependencies (Maven pom.xml, Gradle build.gradle, or the JAR file itself) and note the exact version numberAffected if The version is lower than 2.10.0 (e.g., 2.9.0, 2.8.0, 2.7.0, etc.)
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Search for resolveFile method callsSearch your codebase for invocations of the resolveFile method, particularly focusing on files that handle file path operationsAffected if Your application code calls resolveFile to resolve file paths
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Check for NameScope.DESCENDENT usageInspect the resolveFile calls found and determine whether they explicitly use NameScope.DESCENDENT as the name scope parameterAffected if The code passes NameScope.DESCENDENT to resolveFile, enabling the vulnerable validation path
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Inspect input sources to resolveFileTrace the data flow into resolveFile calls with NameScope.DESCENDENT and determine whether any input originates from external sources (HTTP requests, user uploads, configuration files, or network sources)Affected if External or user-controllable input can reach the resolveFile method with NameScope.DESCENDENT
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Look for URL-encoded traversal sequences in input handlingSearch code that processes file paths for any validation or normalization of URL-encoded sequences like %2E%2E (which represents ..) before passing to resolveFileAffected if Input containing %2E%2E is not validated or rejected before reaching the vulnerable method
You are affected if your application uses Apache Commons VFS versions below 2.10.0 AND utilizes resolveFile with NameScope.DESCENDENT while accepting external input that could contain URL-encoded path traversal sequences (%2E%2E).
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 · scoped2.10.0
Upgrade Apache Commons VFS to version 2.10.0 or later, which contains the fix for properly validating encoded path traversal sequences.
2.10.0
- Identify the current version of Apache Commons VFS in use by checking project dependencies (Maven pom.xml, Gradle build.gradle, or JAR manifest)
- Upgrade Apache Commons VFS dependency to version 2.10.0 or later
- Rebuild and test the application to verify the fix resolves the path traversal issue
- Ensure that any direct usage of FileObject.resolveFile() with NameScope.DESCENDENT now properly rejects URL-encoded path traversal sequences like %2E%2E
Generated from the published advisory — verify against the referenced sources before acting.
Fix this in Commons Vfs
Scoped from the published advisory
- Consultation8.0 h
- Implementation4.0 h
- Testing8.0 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 $6,784.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2025-27553 — 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-2025-27553 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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