changelog: update versions (#21101)

Author: elithrar

src/content/changelog/workers/2025-03-22-next-js-vulnerability-waf.mdx

@@ -12,7 +12,9 @@ date: 2025-03-22T13:00:00Z
 import { Image } from 'astro:assets';
 import managedRuleNextJsAuth from "~/assets/images/changelog/workers/high-res-CVE-2025-29927.gif"
 
-**Update**: We have changed this WAF rule to opt-in only, as sites that use auth middleware with third-party auth vendors were observing failing requests.
+**Update: Mon Mar 24th, 8PM UTC**: Next.js has now [backported the patch for this vulnerability](https://github.com/advisories/GHSA-f82v-jwr5-mffw) to cover Next.js v12 and v13. Users on those versions will need to patch to `13.5.9` and `12.3.5` (respectively) to mitigate the vulnerability.
+
+**Update: Sat Mar 22nd, 4PM UTC**: We have changed this WAF rule to opt-in only, as sites that use auth middleware with third-party auth vendors were observing failing requests.
 
 **We strongly recommend updating your version of Next.js (if eligible)** to the patched versions, as your app will otherwise be vulnerable to an authentication bypass attack regardless of auth provider.
 
@@ -61,6 +63,7 @@ We've made a WAF (Web Application Firewall) rule available to all sites on Cloud
 
 * This managed rule protects sites using Next.js on Workers and Pages, as well as sites using Cloudflare to protect Next.js applications hosted elsewhere.
 * This rule has been made available (but not enabled by default) to all sites as part of our [WAF Managed Ruleset](/waf/managed-rules/reference/cloudflare-managed-ruleset/) and blocks requests that attempt to bypass authentication in Next.js applications.
-* The vulnerability affects almost all Next.js versions, and is patched in Next.js `14.2.25` and `15..2.3`. **Users on older versions of Next.js (`11.1.4` to `13.5.6`) do not have a patch available**.
+* The vulnerability affects almost all Next.js versions, and is patched in Next.js `14.2.25` and `15.2.3`.
+* **Users on older versions of Next.js (`11.1.4` to `13.5.6`) did not originally have a patch available**, but this the patch for this vulnerability has been backported and to Next.js `12.3.5` and `13.5.9` as of Monday, March 24th. Users on Next.js v11 will need to deploy the stated workaround or enable the WAF rule.
 
 The managed WAF rule mitigates this by blocking _external_ user requests with the `x-middleware-subrequest` header regardless of Next.js version, but we recommend users using Next.js 14 and 15 upgrade to the patched versions of Next.js as an additional mitigation.