CVSS 3.1
3.7 lowCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:NCVE-2026-126188 Active Storage: Possible local file disclosure in Active Storage video previews and analysis
Low (3.7) in rails rails. EPSS 0.3% estimated probability of exploitation activity in the next 30 days. Fixed in activestorage 8.0.5.2, 8.1.4.1.
On this page
Active Storage makes it simple to upload and reference files in cloud services and attach those files to Active Record objects. Prior to 8.0.5.2 and from 8.1 until 8.1.4.1, Active Storage's ActiveStorage::Previewer::VideoPreviewer, ActiveStorage::Analyzer::VideoAnalyzer, and ActiveStorage::Analyzer::AudioAnalyzer pass uploaded blob contents to FFmpeg without restricting the demuxer. A direct upload can retain a client-declared video/* or audio/* content type for an HLS playlist. FFmpeg content probing selects the hls demuxer, which opens attacker-named file:// segments when the blob is previewed or analyzed. Applications that accept untrusted uploads and generate video previews or analyze video or audio attachments can disclose a local media file readable by the application process when the attacker knows its path. This issue is fixed in versions 8.0.5.2 and 8.1.4.1.
Severity
- EPSS
- 0.3% estimated probability of exploitation activity in the next 30 days; 21st percentile. Scored 2026-11-13. A forecast for this CVE across the internet, not for your own systems.
- CISA's assessment (SSVC)
- Exploitation: none · Automatable: no · Technical impact: partial, assessed 2026-11-12. From CISA's Vulnrichment in the CVE List: whether it is exploited, whether exploiting it can be automated, and how much control it gives.
- CWE
- CWE-200 Exposure of Sensitive Information to an Unauthorized Actor
- OWASP Top 10
- A01:2025 Broken Access Control
- Published
- Modified
- Assigned by
- GitHub_M (CNA)
- NVD analysis
- Awaiting analysis
- Record from
- the NVD, synced
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Affected
Versions
From the CNA's record in the CVE List.
| Product | Affected |
|---|---|
| rails | >= 8.1, < 8.1.4.1 |
| rails | < 8.0.5.2 |
Fix and patched versions
activestorage(RubyGems): fixed in 8.1.4.1, 8.0.5.2
Packages (OSV)
| Advisory | Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|---|
| GHSA-3f4q-8x5m-76v8 | RubyGems | activestorage | >=8.1.0.beta1 <8.1.4.1 | 8.1.4.1 |
| GHSA-3f4q-8x5m-76v8 | RubyGems | activestorage | <8.0.5.2 | 8.0.5.2 |
Linux distributions
| Distribution | Release | Package | Fixed in | Advisory |
|---|---|---|---|---|
| Debian | 12, 13, 14 | rails | no fix listed | DEBIAN-CVE-2026-126188 |
| Ubuntu | 24.04:LTS, 26.04:LTS, 26.10 and 4 more | rails | no fix listed | UBUNTU-CVE-2026-126188 |
From the distributions' data via OSV.dev: the Debian Security Tracker; Ubuntu Security Notices © Canonical Ltd., CC BY-SA 4.0. Modified: reformatted and linked to CVE records. Credits. On the distributions' own pages: Debian · Ubuntu.
Attack patterns (CAPEC)
The attack patterns MITRE's CAPEC relates to this record's weaknesses, as MITRE names them. Credits. More on the page of CWE-200 (59).
References
- https://github.com/rails/rails/commit/3b1f2627538dc597cd973530c08514a26c2b0282
- https://github.com/rails/rails/commit/69aff80d115bbb9d1e82fd6c6f2fd3ddeafb958b
- https://github.com/rails/rails/releases/tag/v8.0.5.2
- https://github.com/rails/rails/releases/tag/v8.1.4.1
- https://github.com/rails/rails/security/advisories/GHSA-3f4q-8x5m-76v8