diff --git a/package.json b/package.json
index 87eec421591..8966b59b436 100644
--- a/package.json
+++ b/package.json
@@ -178,12 +178,12 @@
         "lint-staged": "^15.1.0",
         "matrix-mock-request": "^2.5.0",
         "matrix-web-i18n": "^3.2.1",
-        "mini-css-extract-plugin": "2.9.0",
+        "mini-css-extract-plugin": "2.9.1",
         "minimist": "^1.2.6",
         "mkdirp": "^3.0.0",
         "modernizr": "^3.12.0",
         "node-fetch": "^2.6.7",
-        "postcss": "8.4.38",
+        "postcss": "8.4.43",
         "postcss-easings": "^4.0.0",
         "postcss-hexrgba": "2.1.0",
         "postcss-import": "16.1.0",
diff --git a/yarn.lock b/yarn.lock
index 41c03b5d575..7fd4a00cfdb 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -8450,10 +8450,10 @@ min-indent@^1.0.0:
   resolved "https://registry.yarnpkg.com/min-indent/-/min-indent-1.0.1.tgz#a63f681673b30571fbe8bc25686ae746eefa9869"
   integrity sha512-I9jwMn07Sy/IwOj3zVkVik2JTvgpaykDZEigL6Rx6N9LbMywwUSMtxET+7lVoDLLd3O3IXwJwvuuns8UB/HeAg==
 
-mini-css-extract-plugin@2.9.0:
-  version "2.9.0"
-  resolved "https://registry.yarnpkg.com/mini-css-extract-plugin/-/mini-css-extract-plugin-2.9.0.tgz#c73a1327ccf466f69026ac22a8e8fd707b78a235"
-  integrity sha512-Zs1YsZVfemekSZG+44vBsYTLQORkPMwnlv+aehcxK/NLKC+EGhDB39/YePYYqx/sTk6NnYpuqikhSn7+JIevTA==
+mini-css-extract-plugin@2.9.1:
+  version "2.9.1"
+  resolved "https://registry.yarnpkg.com/mini-css-extract-plugin/-/mini-css-extract-plugin-2.9.1.tgz#4d184f12ce90582e983ccef0f6f9db637b4be758"
+  integrity sha512-+Vyi+GCCOHnrJ2VPS+6aPoXN2k2jgUzDRhTFLjjTBn23qyXJXkjUWQgTL+mXpF5/A8ixLdCc6kWsoeOjKGejKQ==
   dependencies:
     schema-utils "^4.0.0"
     tapable "^2.2.1"
@@ -9718,13 +9718,13 @@ postcss-value-parser@^4.0.0, postcss-value-parser@^4.1.0, postcss-value-parser@^
   resolved "https://registry.yarnpkg.com/postcss-value-parser/-/postcss-value-parser-4.2.0.tgz#723c09920836ba6d3e5af019f92bc0971c02e514"
   integrity sha512-1NNCs6uurfkVbeXG4S8JFT9t19m45ICnif8zWLd5oPSZ50QnwMfK+H3jv408d4jw/7Bttv5axS5IiHoLaVNHeQ==
 
-postcss@8.4.38:
-  version "8.4.38"
-  resolved "https://registry.yarnpkg.com/postcss/-/postcss-8.4.38.tgz#b387d533baf2054288e337066d81c6bee9db9e0e"
-  integrity sha512-Wglpdk03BSfXkHoQa3b/oulrotAkwrlLDRSOb9D0bN86FdRyE9lppSp33aHNPgBa0JKCoB+drFLZkQoRRYae5A==
+postcss@8.4.43:
+  version "8.4.43"
+  resolved "https://registry.yarnpkg.com/postcss/-/postcss-8.4.43.tgz#a5ddf22f4cc38e64c6ae030182b43e539d316419"
+  integrity sha512-gJAQVYbh5R3gYm33FijzCZj7CHyQ3hWMgJMprLUlIYqCwTeZhBQ19wp0e9mA25BUbEvY5+EXuuaAjqQsrBxQBQ==
   dependencies:
     nanoid "^3.3.7"
-    picocolors "^1.0.0"
+    picocolors "^1.0.1"
     source-map-js "^1.2.0"
 
 postcss@^8.3.11, postcss@^8.4.33, postcss@^8.4.38: