CVE-2026-126188: rails · Information Exposure
Affects railsSource CVE Database V5
Not known to be exploited · CVSS 3.7 Low : upgrade to 8.1.4.1 or 8.0.5.2 when convenient.
Data as of 11 Nov 2026, 00:06 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 10 Nov 2026.
What to do
Upgrade rails to 8.1.4.1 or 8.0.5.2.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| railsrails | Affected
| Fixed in
|
| railsrails | Affected
| Fixed in
|
AI-suggested
Upgrade Rails to version 8.0.5.2 or later if using the 8.0.x series, or to version 8.1.4.1 or later if using the 8.1.x series. These versions include fixes that restrict the FFmpeg demuxer usage and prevent local file disclosure. No other mitigation is indicated by the vendor advisory.
Description
A vulnerability in Ruby on Rails Active Storage prior to versions 8.0.5.2 and between 8.1 and 8.1.4.1 allows exposure of local media files. This occurs because certain Active Storage components pass uploaded blob contents to FFmpeg without restricting the demuxer, enabling an attacker to craft uploads that cause FFmpeg to open local file segments. This can disclose local files readable by the application process if the attacker knows the file path.
References
- github.com/rails/rails/security/advisories/GHSA-3f4q-8x5m-76v8 (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/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)