diff --git a/xtest/pyproject.toml b/xtest/pyproject.toml
index 297da6a6..be56df68 100644
--- a/xtest/pyproject.toml
+++ b/xtest/pyproject.toml
@@ -16,7 +16,7 @@ classifiers = [
 dependencies = [
     "annotated-types>=0.7.0",
     "attrs>=25.4.0",
-    "certifi>=2026.1.4",
+    "certifi>=2026.5.20",
     "cffi>=2.0.0",
     "charset-normalizer>=3.4.4",
     "construct>=2.10.70",
diff --git a/xtest/uv.lock b/xtest/uv.lock
index 7533f33c..4075465e 100644
--- a/xtest/uv.lock
+++ b/xtest/uv.lock
@@ -22,11 +22,11 @@ wheels = [
 
 [[package]]
 name = "certifi"
-version = "2026.1.4"
+version = "2026.5.20"
 source = { registry = "https://pypi.org/simple" }
-sdist = { url = "https://files.pythonhosted.org/packages/e0/2d/a891ca51311197f6ad14a7ef42e2399f36cf2f9bd44752b3dc4eab60fdc5/certifi-2026.1.4.tar.gz", hash = "sha256:ac726dd470482006e014ad384921ed6438c457018f4b3d204aea4281258b2120", size = 154268, upload-time = "2026-01-04T02:42:41.825Z" }
+sdist = { url = "https://files.pythonhosted.org/packages/f3/ce/ee2ecad540810a79593028e88299baeae54d346cc7a0d94b6199988b89b1/certifi-2026.5.20.tar.gz", hash = "sha256:69dea482ab64caa7b9f6aba1c6bf48bb6a5448d1c0f1b17ab42ad8c763a5344d", size = 135422, upload-time = "2026-05-20T11:46:50.073Z" }
 wheels = [
-    { url = "https://files.pythonhosted.org/packages/e6/ad/3cc14f097111b4de0040c83a525973216457bbeeb63739ef1ed275c1c021/certifi-2026.1.4-py3-none-any.whl", hash = "sha256:9943707519e4add1115f44c2bc244f782c0249876bf51b6599fee1ffbedd685c", size = 152900, upload-time = "2026-01-04T02:42:40.15Z" },
+    { url = "https://files.pythonhosted.org/packages/59/8c/57e832b7af6d7c5abe66eb3fbe3a3a32f4d11ea23a1aa7131371035be991/certifi-2026.5.20-py3-none-any.whl", hash = "sha256:3c52e209ba0a4ad7aebe60436a4ab349c39e1e602e8c134221e546902ad25897", size = 134134, upload-time = "2026-05-20T11:46:48.578Z" },
 ]
 
 [[package]]
@@ -636,7 +636,7 @@ dev = [
 requires-dist = [
     { name = "annotated-types", specifier = ">=0.7.0" },
     { name = "attrs", specifier = ">=25.4.0" },
-    { name = "certifi", specifier = ">=2026.1.4" },
+    { name = "certifi", specifier = ">=2026.5.20" },
     { name = "cffi", specifier = ">=2.0.0" },
     { name = "charset-normalizer", specifier = ">=3.4.4" },
     { name = "construct", specifier = ">=2.10.70" },