Linkify MSC and CVE in the changelog

Author: anoadragon453

CHANGES.md

@@ -4,7 +4,7 @@
 
 - Fix a bug which could corrupt auth chains making it impossible to perform state resolution. ([\#18746](https://github.com/element-hq/synapse/issues/18746))
 - Fix error message in `register_new_matrix_user` utility script for empty `registration_shared_secret`. ([\#18780](https://github.com/element-hq/synapse/issues/18780))
-- Allow enabling MSC4108 when the stable Matrix Authentication Service integration is enabled. ([\#18832](https://github.com/element-hq/synapse/issues/18832))
+- Allow enabling [MSC4108](https://github.com/matrix-org/matrix-spec-proposals/pull/4108) when the stable Matrix Authentication Service integration is enabled. ([\#18832](https://github.com/element-hq/synapse/issues/18832))
 
 ### Improved Documentation
 
@@ -15,7 +15,7 @@
 - Update tests to ensure all database tables are emptied when purging a room. ([\#18794](https://github.com/element-hq/synapse/issues/18794))
 - Instrument the `encode_response` part of Sliding Sync requests for more complete traces in Jaeger. ([\#18815](https://github.com/element-hq/synapse/issues/18815))
 - Tag Sliding Sync traces when we `wait_for_events`. ([\#18816](https://github.com/element-hq/synapse/issues/18816))
-- Fix `portdb` CI by hardcoding the new `pg_dump` restrict key that was added due to CVE-2025-8714. ([\#18824](https://github.com/element-hq/synapse/issues/18824))
+- Fix `portdb` CI by hardcoding the new `pg_dump` restrict key that was added due to [CVE-2025-8714](https://nvd.nist.gov/vuln/detail/cve-2025-8714). ([\#18824](https://github.com/element-hq/synapse/issues/18824))