Unauthenticated file disclosure via prefix containment check
Published May 26, 2026 · Updated May 26, 2026
Path traversal in ViewComponent 3.0.0 and later before 4.9.0 allows remote attackers to read files through the system test entrypoint. The controller resolves the file parameter with File.realpath but accepts any resolved path whose string begins with the temporary-directory path, so a same-prefix sibling path passes and is rendered. The route exists only in Rails test mode, limiting exposure to shared CI, staging, review applications, or accidentally exposed test deployments.
Summary
What happened
Path traversal in ViewComponent 3.0.0 and later before 4.9.0 allows remote attackers to read files through the system test entrypoint. The controller resolves the file parameter with File.realpath but accepts any resolved path whose string begins with the temporary-directory path, so a same-prefix sibling path passes and is rendered. The route exists only in Rails test mode, limiting exposure to shared CI, staging, review applications, or accidentally exposed test deployments.
The record
- CVE
- CVE-2026-44837
- Published
- May 26, 2026
- Updated
- May 26, 2026
- Vendor
- ViewComponent
- Product
- ViewComponent
- Classifications
- CWE-187, T1190
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- May 26, 2026CVE publishedPublication date reported by the CVE source.
- May 26, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=>= 3.0.0, < 4.9.0
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Public exploit references
- System test entrypoint sibling-directory PoC testproof of concept · demonstrated
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
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Your stack
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