Description
Action Pack is a framework for handling and responding to web requests. Prior to 8.1.4.1 and 8.0.5.2, Action Pack session stores other than ActionDispatch::Session::CookieStore (CacheStore, MemCacheStore, and third-party stores built on AbstractStore, AbstractSecureStore or the session mixins) write the session cookie without a SameSite attribute, regardless of config.action_dispatch.cookies_same_site_protection, which defaults to :lax. Only CookieStore applies the configured policy. In browsers that do not treat a cookie without the attribute as SameSite=Lax, a cross-site request could carry the session cookie, possibly leading to cross-site request forgery against actions that do not verify an authenticity token, such as those of API-only applications. Applications are affected when they use a session store other than CookieStore and do not pass same_site: to config.session_store. This issue is fixed in versions 8.1.4.1 and 8.0.5.2.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| rails | rails | >= 8.1, < 8.1.4.1, < 8.0.5.2 | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | rails | No fix yet | — |
| Debian 13 | rails | No fix yet | — |
| Debian 12 | rails | No fix yet | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | rails | No fix yet | — |
| Ubuntu 26.04 LTS | rails | No fix yet | — |
| Ubuntu 24.04 LTS | rails | No fix yet | — |
Show 4 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 22.04 LTS | rails | No fix yet | — |
| Ubuntu Pro 20.04 LTS | rails | No fix yet | — |
| Ubuntu Pro 18.04 LTS | rails | No fix yet | — |
| Ubuntu Pro 16.04 LTS | rails | No fix yet | — |
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| RubyGems | actionpack | >= 8.1.0.beta1, < 8.1.4.1 | 8.1.4.1 | GHSA-gmj8-hvj3-49mw |
| RubyGems | actionpack | < 8.0.5.2 | 8.0.5.2 | GHSA-gmj8-hvj3-49mw |
Advisories 1
- WID-SEC-2026-4317 Ruby on Rails: Mehrere Schwachstellen BSI CERT-Bund (WID) · Nov 10, 2026
References
- https://github.com/rails/rails/security/advisories/GHSA-gmj8-hvj3-49mw
- https://github.com/rails/rails/commit/2d9f502df941e31ce9bad0e846564f49396bed46
- https://github.com/rails/rails/commit/f2392996be723708271a8d30bfcf0edc221e53ef
- https://github.com/rails/rails/releases/tag/v8.0.5.2
- https://github.com/rails/rails/releases/tag/v8.1.4.1