Vulnerability in Hotwired Turbo
CVE-2025-66803
Race condition in the turbo-frame element handler in Hotwired Turbo before 8.0.x causes logout operations to fail when delayed frame responses reapply session cookies after logout. This can be exploited by remote attackers via selective network delays (e.g. delaying requests based on sequence or timing) or by physically proximate attackers when the race condition occurs naturally on shared computers.
Vulnerability class: Race Condition
Published · last modified .
CVSS v3 metric
CVSS v3 base score 4.8 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N.
EPSS exploit prediction
EPSS: 0.003 (18.1th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 18th percentile — 18.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: +0.000
Affected products
Weakness classification (CWE)
Public proof-of-concept exploits
References
- github.com/hotwired/turbo/pull/1399 (Exploit, Patch, Issue Tracking)
- turbo.hotwired.dev/handbook/frames (Product)
- github.com/hotwired/turbo/security/advisories/GHSA-qppm-g56g-fpvp (Vendor Advisory)
Frequently asked questions
- What is CVE-2025-66803?
- CVE-2025-66803 is a medium-severity vulnerability in Hotwired Turbo, classified under Concurrent Execution using Shared Resource with Improper Synchronization (Race Condition). CVSS score: 4.8/10. Published 2026-01-20.
- How severe is CVE-2025-66803?
- Medium severity. CVSS v3 base score is 4.8 out of 10.
- Is CVE-2025-66803 known to be exploited?
- 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.