diff --git a/Cargo.lock b/Cargo.lock
index 48376f542a8..7431424346e 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -5065,7 +5065,7 @@ dependencies = [
 [[package]]
 name = "ruma"
 version = "0.10.1"
-source = "git+https://github.com/matrix-org/ruma?rev=79289381444e886c454302e1e8f5b5f62f249a57#79289381444e886c454302e1e8f5b5f62f249a57"
+source = "git+https://github.com/matrix-org/ruma?rev=e87f1d839e3821f0fb0ba20fb3164fedbc90a25c#e87f1d839e3821f0fb0ba20fb3164fedbc90a25c"
 dependencies = [
  "assign",
  "js_int",
@@ -5082,7 +5082,7 @@ dependencies = [
 [[package]]
 name = "ruma-client-api"
 version = "0.18.0"
-source = "git+https://github.com/matrix-org/ruma?rev=79289381444e886c454302e1e8f5b5f62f249a57#79289381444e886c454302e1e8f5b5f62f249a57"
+source = "git+https://github.com/matrix-org/ruma?rev=e87f1d839e3821f0fb0ba20fb3164fedbc90a25c#e87f1d839e3821f0fb0ba20fb3164fedbc90a25c"
 dependencies = [
  "as_variant",
  "assign",
@@ -5105,7 +5105,7 @@ dependencies = [
 [[package]]
 name = "ruma-common"
 version = "0.13.0"
-source = "git+https://github.com/matrix-org/ruma?rev=79289381444e886c454302e1e8f5b5f62f249a57#79289381444e886c454302e1e8f5b5f62f249a57"
+source = "git+https://github.com/matrix-org/ruma?rev=e87f1d839e3821f0fb0ba20fb3164fedbc90a25c#e87f1d839e3821f0fb0ba20fb3164fedbc90a25c"
 dependencies = [
  "as_variant",
  "base64 0.22.1",
@@ -5137,7 +5137,7 @@ dependencies = [
 [[package]]
 name = "ruma-events"
 version = "0.28.1"
-source = "git+https://github.com/matrix-org/ruma?rev=79289381444e886c454302e1e8f5b5f62f249a57#79289381444e886c454302e1e8f5b5f62f249a57"
+source = "git+https://github.com/matrix-org/ruma?rev=e87f1d839e3821f0fb0ba20fb3164fedbc90a25c#e87f1d839e3821f0fb0ba20fb3164fedbc90a25c"
 dependencies = [
  "as_variant",
  "indexmap 2.2.6",
@@ -5162,7 +5162,7 @@ dependencies = [
 [[package]]
 name = "ruma-federation-api"
 version = "0.9.0"
-source = "git+https://github.com/matrix-org/ruma?rev=79289381444e886c454302e1e8f5b5f62f249a57#79289381444e886c454302e1e8f5b5f62f249a57"
+source = "git+https://github.com/matrix-org/ruma?rev=e87f1d839e3821f0fb0ba20fb3164fedbc90a25c#e87f1d839e3821f0fb0ba20fb3164fedbc90a25c"
 dependencies = [
  "http 1.1.0",
  "js_int",
@@ -5176,7 +5176,7 @@ dependencies = [
 [[package]]
 name = "ruma-html"
 version = "0.2.0"
-source = "git+https://github.com/matrix-org/ruma?rev=79289381444e886c454302e1e8f5b5f62f249a57#79289381444e886c454302e1e8f5b5f62f249a57"
+source = "git+https://github.com/matrix-org/ruma?rev=e87f1d839e3821f0fb0ba20fb3164fedbc90a25c#e87f1d839e3821f0fb0ba20fb3164fedbc90a25c"
 dependencies = [
  "as_variant",
  "html5ever",
@@ -5188,7 +5188,7 @@ dependencies = [
 [[package]]
 name = "ruma-identifiers-validation"
 version = "0.9.5"
-source = "git+https://github.com/matrix-org/ruma?rev=79289381444e886c454302e1e8f5b5f62f249a57#79289381444e886c454302e1e8f5b5f62f249a57"
+source = "git+https://github.com/matrix-org/ruma?rev=e87f1d839e3821f0fb0ba20fb3164fedbc90a25c#e87f1d839e3821f0fb0ba20fb3164fedbc90a25c"
 dependencies = [
  "js_int",
  "thiserror",
@@ -5197,7 +5197,7 @@ dependencies = [
 [[package]]
 name = "ruma-macros"
 version = "0.13.0"
-source = "git+https://github.com/matrix-org/ruma?rev=79289381444e886c454302e1e8f5b5f62f249a57#79289381444e886c454302e1e8f5b5f62f249a57"
+source = "git+https://github.com/matrix-org/ruma?rev=e87f1d839e3821f0fb0ba20fb3164fedbc90a25c#e87f1d839e3821f0fb0ba20fb3164fedbc90a25c"
 dependencies = [
  "once_cell",
  "proc-macro-crate",
@@ -5212,7 +5212,7 @@ dependencies = [
 [[package]]
 name = "ruma-push-gateway-api"
 version = "0.9.0"
-source = "git+https://github.com/matrix-org/ruma?rev=79289381444e886c454302e1e8f5b5f62f249a57#79289381444e886c454302e1e8f5b5f62f249a57"
+source = "git+https://github.com/matrix-org/ruma?rev=e87f1d839e3821f0fb0ba20fb3164fedbc90a25c#e87f1d839e3821f0fb0ba20fb3164fedbc90a25c"
 dependencies = [
  "js_int",
  "ruma-common",
diff --git a/Cargo.toml b/Cargo.toml
index cc3c89556eb..57da932622e 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -47,7 +47,7 @@ once_cell = "1.16.0"
 pin-project-lite = "0.2.9"
 rand = "0.8.5"
 reqwest = { version = "0.12.4", default-features = false }
-ruma = { git = "https://github.com/matrix-org/ruma", rev = "79289381444e886c454302e1e8f5b5f62f249a57", features = [
+ruma = { git = "https://github.com/matrix-org/ruma", rev = "e87f1d839e3821f0fb0ba20fb3164fedbc90a25c", features = [
     "client-api-c",
     "compat-upload-signatures",
     "compat-user-id",
@@ -61,7 +61,7 @@ ruma = { git = "https://github.com/matrix-org/ruma", rev = "79289381444e886c4543
     "unstable-msc4075",
     "unstable-msc4140",
 ] }
-ruma-common = { git = "https://github.com/matrix-org/ruma", rev = "79289381444e886c454302e1e8f5b5f62f249a57" }
+ruma-common = { git = "https://github.com/matrix-org/ruma", rev = "e87f1d839e3821f0fb0ba20fb3164fedbc90a25c" }
 serde = "1.0.151"
 serde_html_form = "0.2.0"
 serde_json = "1.0.91"
diff --git a/crates/matrix-sdk-base/src/rooms/mod.rs b/crates/matrix-sdk-base/src/rooms/mod.rs
index 738d5110116..264e00052fb 100644
--- a/crates/matrix-sdk-base/src/rooms/mod.rs
+++ b/crates/matrix-sdk-base/src/rooms/mod.rs
@@ -40,7 +40,7 @@ use ruma::{
         RedactedStateEventContent, StaticStateEventContent, SyncStateEvent,
     },
     room::RoomType,
-    EventId, OwnedUserId, RoomVersionId,
+    EventId, OwnedUserId, RoomVersionId, UserId,
 };
 use serde::{Deserialize, Serialize};
 
@@ -195,9 +195,12 @@ impl BaseRoomInfo {
                 let mut o_ev = o_ev.clone();
                 o_ev.content.set_created_ts_if_none(o_ev.origin_server_ts);
 
+                let Some(owned_user_id) = get_user_id_for_state_key(m.state_key()) else {
+                    return false;
+                };
+
                 // add the new event.
-                self.rtc_member
-                    .insert(m.state_key().clone(), SyncStateEvent::Original(o_ev).into());
+                self.rtc_member.insert(owned_user_id, SyncStateEvent::Original(o_ev).into());
 
                 // Remove all events that don't contain any memberships anymore.
                 self.rtc_member.retain(|_, ev| {
@@ -319,6 +322,33 @@ impl BaseRoomInfo {
     }
 }
 
+/// Extract a user ID from a state key that matches one of these formats:
+/// - `<user ID>`
+/// - `<user ID>_<string>`
+/// - `_<user ID>_<string>`
+fn get_user_id_for_state_key(state_key: &str) -> Option<OwnedUserId> {
+    if let Ok(user_id) = UserId::parse(state_key) {
+        return Some(user_id);
+    }
+
+    // Ignore leading underscore if present
+    // (used for avoiding auth rules on @-prefixed state keys)
+    let state_key = state_key.strip_prefix('_').unwrap_or(state_key);
+    if state_key.starts_with('@') {
+        if let Some(colon_idx) = state_key.find(':') {
+            let state_key_user_id = match state_key[colon_idx + 1..].find('_') {
+                None => state_key,
+                Some(suffix_idx) => &state_key[..colon_idx + 1 + suffix_idx],
+            };
+            if let Ok(user_id) = UserId::parse(state_key_user_id) {
+                return Some(user_id);
+            }
+        }
+    }
+
+    None
+}
+
 bitflags! {
     /// Notable tags, i.e. subset of tags that we are more interested by.
     ///
@@ -536,9 +566,12 @@ impl RoomMemberships {
 mod tests {
     use std::ops::Not;
 
-    use ruma::events::tag::{TagInfo, TagName, Tags};
+    use ruma::{
+        events::tag::{TagInfo, TagName, Tags},
+        user_id,
+    };
 
-    use super::{BaseRoomInfo, RoomNotableTags};
+    use super::{get_user_id_for_state_key, BaseRoomInfo, RoomNotableTags};
 
     #[test]
     fn test_handle_notable_tags_favourite() {
@@ -569,4 +602,32 @@ mod tests {
         base_room_info.handle_notable_tags(&tags);
         assert!(base_room_info.notable_tags.contains(RoomNotableTags::LOW_PRIORITY).not());
     }
+
+    #[test]
+    fn test_get_user_id_for_state_key() {
+        assert!(get_user_id_for_state_key("").is_none());
+        assert!(get_user_id_for_state_key("abc").is_none());
+        assert!(get_user_id_for_state_key("@nocolon").is_none());
+        assert!(get_user_id_for_state_key("@noserverpart:").is_none());
+        assert!(get_user_id_for_state_key("@noserverpart:_suffix").is_none());
+
+        let user_id = user_id!("@username:example.org");
+
+        assert_eq!(get_user_id_for_state_key(user_id.as_str()).as_deref(), Some(user_id));
+        assert_eq!(
+            get_user_id_for_state_key(format!("{user_id}_valid_suffix").as_str()).as_deref(),
+            Some(user_id)
+        );
+        assert!(get_user_id_for_state_key(format!("{user_id}:invalid_suffix").as_str()).is_none());
+
+        assert_eq!(
+            get_user_id_for_state_key(format!("_{user_id}").as_str()).as_deref(),
+            Some(user_id)
+        );
+        assert_eq!(
+            get_user_id_for_state_key(format!("_{user_id}_valid_suffix").as_str()).as_deref(),
+            Some(user_id)
+        );
+        assert!(get_user_id_for_state_key(format!("_{user_id}:invalid_suffix").as_str()).is_none());
+    }
 }
diff --git a/crates/matrix-sdk-base/src/rooms/normal.rs b/crates/matrix-sdk-base/src/rooms/normal.rs
index 581d8dacae9..52fae8e89d8 100644
--- a/crates/matrix-sdk-base/src/rooms/normal.rs
+++ b/crates/matrix-sdk-base/src/rooms/normal.rs
@@ -2624,7 +2624,7 @@ mod tests {
             // we can simply use now here since this will be dropped when using a MinimalStateEvent
             // in the roomInfo
             origin_server_ts: timestamp(0),
-            state_key: user_id.to_owned(),
+            state_key: user_id.to_string(),
             unsigned: StateUnsigned::new(),
         }))
     }