CVE-2026-126188: Active Storage · Possible local file disclosure in video previews and analysis
Affects activestorageSource GCVE Database
Not known to be exploited · CVSS 3.7 Low : upgrade to 8.1.4.1 when convenient.
Data as of 12 Nov 2026, 22:23 UTC
Thin evidence
One scorer or none| CNA (GitHub_M) | CVSS 3.1 | 3.7 |
|---|
- Patch
- Available – fixed in 8.1.4.1, 8.0.5.2
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:NExploitation evidence
Disclosed: evidence found.
CVE published 10 Nov 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 12 Nov 2026.
What to do
Upgrade activestorage to 8.1.4.1; activestorage to 8.0.5.2.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| RubyGemsactivestorage | Affected
| Fixed in
|
| RubyGemsactivestorage | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Upgrade to Active Storage versions 8.1.4.1 or 8.0.5.2 or later where the vulnerability is fixed by restricting FFmpeg allowed formats. For applications unable to upgrade immediately, disable the VideoPreviewer, VideoAnalyzer, and AudioAnalyzer components in Active Storage configuration to prevent FFmpeg execution on uploaded files.
Description
Active Storage versions before 8.1.4.1 and 8.0.5.2 allow local file disclosure via video previews and analysis. The vulnerability arises because FFmpeg tools run on uploaded blobs without restricting input formats, enabling crafted HLS playlists to cause disclosure of local media files accessible by the application process. This affects applications accepting untrusted uploads and generating video previews or media metadata using FFmpeg. Fixed releases restrict FFmpeg to allowed formats via configuration. Workarounds include disabling video and audio previewers and analyzers.
References
- github.com/rails/rails/security/advisories/GHSA-3f4q-8x5m-76v8 (opens in a new tab)
- nvd.nist.gov/vuln/detail/CVE-2026-126188 (opens in a new tab)
- github.com/rails/rails/commit/3b1f2627538dc597cd973530c08514a26c2b0282 (opens in a new tab)
- github.com/rails/rails/commit/69aff80d115bbb9d1e82fd6c6f2fd3ddeafb958b (opens in a new tab)
- github.com/rails/rails (opens in a new tab)
- github.com/rails/rails/releases/tag/v8.0.5.2 (opens in a new tab)
- github.com/rails/rails/releases/tag/v8.1.4.1 (opens in a new tab)
- github.com/rubysec/ruby-advisory-db/blob/master/gems/activestorage/GHSA-3f4q-8x5m-76v8.yml (opens in a new tab)