diff --git a/CHANGELOG.md b/CHANGELOG.md
index 2c4964060d..eb6733b9f5 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,13 @@
 
 ## main / unreleased
 
+## 3.5.2 / 2026-04-13
+
+This release has a fix for a Stored XSS vulnerability that can be triggered via crafted metric names and label values in Prometheus web UI tooltips and metrics explorer. Thanks to Duc Anh Nguyen from TinyxLab for reporting it.
+
+* [SECURITY] UI: Fix stored XSS via unescaped metric names and labels. CVE-2026-40179. #18507
+* [PERF] Regex: Stop calling Simplify. #17908
+
 ## 3.5.1 / 2026-01-07
 
 No code changes, just some dependency updates:
diff --git a/VERSION b/VERSION
index d5c0c99142..87ce492908 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-3.5.1
+3.5.2
diff --git a/web/ui/mantine-ui/package.json b/web/ui/mantine-ui/package.json
index 4a7035f3a5..d1d10be5bd 100644
--- a/web/ui/mantine-ui/package.json
+++ b/web/ui/mantine-ui/package.json
@@ -1,7 +1,7 @@
 {
   "name": "@prometheus-io/mantine-ui",
   "private": true,
-  "version": "0.305.1",
+  "version": "0.305.2",
   "type": "module",
   "scripts": {
     "start": "vite",
@@ -28,7 +28,7 @@
     "@microsoft/fetch-event-source": "^2.0.1",
     "@nexucis/fuzzy": "^0.5.1",
     "@nexucis/kvsearch": "^0.9.1",
-    "@prometheus-io/codemirror-promql": "0.305.1",
+    "@prometheus-io/codemirror-promql": "0.305.2",
     "@reduxjs/toolkit": "^2.7.0",
     "@tabler/icons-react": "^3.31.0",
     "@tanstack/react-query": "^5.74.7",
diff --git a/web/ui/module/codemirror-promql/package.json b/web/ui/module/codemirror-promql/package.json
index 2cbd623da1..4fe240c97f 100644
--- a/web/ui/module/codemirror-promql/package.json
+++ b/web/ui/module/codemirror-promql/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@prometheus-io/codemirror-promql",
-  "version": "0.305.1",
+  "version": "0.305.2",
   "description": "a CodeMirror mode for the PromQL language",
   "types": "dist/esm/index.d.ts",
   "module": "dist/esm/index.js",
@@ -29,7 +29,7 @@
   },
   "homepage": "https://github.com/prometheus/prometheus/blob/main/web/ui/module/codemirror-promql/README.md",
   "dependencies": {
-    "@prometheus-io/lezer-promql": "0.305.1",
+    "@prometheus-io/lezer-promql": "0.305.2",
     "lru-cache": "^11.1.0"
   },
   "devDependencies": {
diff --git a/web/ui/module/lezer-promql/package.json b/web/ui/module/lezer-promql/package.json
index ad0cb7db90..f3c2eb3bf4 100644
--- a/web/ui/module/lezer-promql/package.json
+++ b/web/ui/module/lezer-promql/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@prometheus-io/lezer-promql",
-  "version": "0.305.1",
+  "version": "0.305.2",
   "description": "lezer-based PromQL grammar",
   "main": "dist/index.cjs",
   "type": "module",
diff --git a/web/ui/package-lock.json b/web/ui/package-lock.json
index c3310156cd..e8310de400 100644
--- a/web/ui/package-lock.json
+++ b/web/ui/package-lock.json
@@ -1,12 +1,12 @@
 {
   "name": "prometheus-io",
-  "version": "0.305.1",
+  "version": "0.305.2",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
       "name": "prometheus-io",
-      "version": "0.305.1",
+      "version": "0.305.2",
       "workspaces": [
         "mantine-ui",
         "module/*"
@@ -24,7 +24,7 @@
     },
     "mantine-ui": {
       "name": "@prometheus-io/mantine-ui",
-      "version": "0.305.1",
+      "version": "0.305.2",
       "dependencies": {
         "@codemirror/autocomplete": "^6.18.6",
         "@codemirror/language": "^6.11.0",
@@ -42,7 +42,7 @@
         "@microsoft/fetch-event-source": "^2.0.1",
         "@nexucis/fuzzy": "^0.5.1",
         "@nexucis/kvsearch": "^0.9.1",
-        "@prometheus-io/codemirror-promql": "0.305.1",
+        "@prometheus-io/codemirror-promql": "0.305.2",
         "@reduxjs/toolkit": "^2.7.0",
         "@tabler/icons-react": "^3.31.0",
         "@tanstack/react-query": "^5.74.7",
@@ -189,10 +189,10 @@
     },
     "module/codemirror-promql": {
       "name": "@prometheus-io/codemirror-promql",
-      "version": "0.305.1",
+      "version": "0.305.2",
       "license": "Apache-2.0",
       "dependencies": {
-        "@prometheus-io/lezer-promql": "0.305.1",
+        "@prometheus-io/lezer-promql": "0.305.2",
         "lru-cache": "^11.1.0"
       },
       "devDependencies": {
@@ -222,7 +222,7 @@
     },
     "module/lezer-promql": {
       "name": "@prometheus-io/lezer-promql",
-      "version": "0.305.1",
+      "version": "0.305.2",
       "license": "Apache-2.0",
       "devDependencies": {
         "@lezer/generator": "^1.7.3",
diff --git a/web/ui/package.json b/web/ui/package.json
index 2a8f963fba..a9b83625cb 100644
--- a/web/ui/package.json
+++ b/web/ui/package.json
@@ -1,7 +1,7 @@
 {
   "name": "prometheus-io",
   "description": "Monorepo for the Prometheus UI",
-  "version": "0.305.1",
+  "version": "0.305.2",
   "private": true,
   "scripts": {
     "build": "bash build_ui.sh --all",