Katalyst Koi: Session cookies can be replayed after user logout
Priority LOW 34CWE-613Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- High
- Impact type
- Security bypass
- Confidentiality · integrity · availability
- High · High · None
- Fix status
- Fixed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub. Impact type from CWE-613.
Summary
Katalyst Koi is a framework for building Rails admin functionality. Prior to 4.20.0 and 5.6.0, admin session cookies were not invalidated when an admin user logged out. An attacker with access to a valid admin session cookie could continue to access admin functionality after logout, until the cookie expired or session secrets were rotated. This vulnerability is fixed in 4.20.0 and 5.6.0.
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00197 9th percentileScored 2026-11-07
Fix Fixed koi (katalyst): 4.20.0katalyst-koi (RubyGems): 4.20.0, 5.6.0
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Total
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| katalyst | koi | before 4.20.0; >= 5.0.0 <= 5.6.0 | 4.20.0 | Patch available | CNA |
| — | katalyst-koi (RubyGems) | before 4.20.0 | 4.20.0 | Patch available | GHSA-4cx3-3c38-j9vv |
| — | katalyst-koi (RubyGems) | 5.0.0 to before 5.6.0 | 5.6.0 | Patch available | GHSA-4cx3-3c38-j9vv |
- koi Vendorkatalyst Affected before 4.20.0; >= 5.0.0 <= 5.6.0 Fixed in 4.20.0 Patch available CNA
- katalyst-koi (RubyGems) Vendor— Affected before 4.20.0 Fixed in 4.20.0 Patch available GHSA-4cx3-3c38-j9vv
- katalyst-koi (RubyGems) Vendor— Affected 5.0.0 to before 5.6.0 Fixed in 5.6.0 Patch available GHSA-4cx3-3c38-j9vv
Remediation
- Fix · CNA koi (katalyst) Fixed in 4.20.0
- Fix · GHSA-4cx3-3c38-j9vv katalyst-koi (RubyGems) Fixed in 4.20.0 Advisory →
- Fix · GHSA-4cx3-3c38-j9vv katalyst-koi (RubyGems) Fixed in 5.6.0 Advisory →
Timeline
- 2026-10-02 Threatist record created from CVE-2026-44511
- 2026-10-03 Alias added: GHSA-4cx3-3c38-j9vv
References
Sources
- CVE-2026-44511 · CVE Program
- CVE-2026-44511 · NVD
- FIRST EPSS
- GHSA-4cx3-3c38-j9vv · GitHub Advisory Database · CC BY 4.0
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