Answer in brief
CVE-2025-46336 records a Medium severity (CVSS 4.2) vulnerability in Rack session gets restored after deletion. The current sources do not mark it as known exploited. The current feed maps rack-session (rubygems). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 4.2. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps rack-session (rubygems). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| rack-sessionrubygems | >=2.0.0 <2.1.1 | 2.1.1 |
Published upstream
May 8, 2025
Evidence: source:osv:source_dates:source-dates:recordSource modified
Sep 10, 2026
Evidence: source:osv:source_dates:source-dates:recordFirst seen by HOL
Aug 7, 2026
## Summary When using the `Rack::Session::Pool` middleware, simultaneous rack requests can restore a deleted rack session, which allows the unauthenticated user to occupy that session. ## Details [Rack session middleware](https://github.com/rack/rack-session/blob/v2.1.0/lib/rack/session/abstract/id.rb#L271-L278) prepares the session at the beginning of request, then saves is back to the store with possible changes applied by host rack application. This way the session becomes to be a subject of race conditions in general sense over concurrent rack requests. ## Impact When using the `Rack::Session::Pool` middleware, and provided the attacker can acquire a session cookie (already a major issue), the session may be restored if the attacker can trigger a long running request (within that same session) adjacent to the user logging out, in order to retain illicit access even after a user has attempted to logout. ## Mitigation - Update to the latest version of `rack-session`, or - Ensure your application invalidates sessions atomically by marking them as logged out e.g., using a `logged_out` flag, instead of deleting them, and check this flag on every request to prevent reuse, or - Implement a custom session store that tracks session invalidation timestamps and refuses to accept session data if the session was invalidated after the request began. ## Related This code was previously part of `rack` in Rack < 3, see <https://github.com/rack/rack/security/advisories/GHSA-vpfw-47h7-xj4g> for the equivalent advisory in `rack` (affecting Rack < 3 only).
Quoted source text, attributed separately from HOL analysis.