diff --git a/tests/test_phase4.cpp b/tests/test_phase4.cpp
index f355501..22727fb 100644
--- a/tests/test_phase4.cpp
+++ b/tests/test_phase4.cpp
@@ -5300,8 +5300,11 @@ void testXmrigAssetSelection()
     EXPECT_TRUE(linux >= 0);
     EXPECT_TRUE(win >= 0);
     EXPECT_TRUE(linux != win);
-    EXPECT_TRUE(rel.assets[linux].name.find("linux-x64.zip") != std::string::npos);
-    EXPECT_TRUE(rel.assets[win].name.find("win-x64.zip") != std::string::npos);
+    // Guard the index reads: select*Asset returns -1 when nothing matches, and EXPECT_TRUE doesn't
+    // abort this harness, so an unguarded rel.assets[-1] on a fixture/parser regression would SIGSEGV
+    // the whole suite instead of reporting the failed EXPECT above.
+    if (linux >= 0) EXPECT_TRUE(rel.assets[linux].name.find("linux-x64.zip") != std::string::npos);
+    if (win >= 0)   EXPECT_TRUE(rel.assets[win].name.find("win-x64.zip") != std::string::npos);
     // No macOS build in this fixture -> graceful "not found".
     EXPECT_EQ(selectXmrigAsset(rel, "macos-x86_64"), -1);
     EXPECT_EQ(selectXmrigAsset(rel, "macos-arm64"), -1);
@@ -5607,9 +5610,11 @@ void testDaemonAssetSelection()
     const int win = selectDaemonAsset(rel, "win64");
     EXPECT_TRUE(lin >= 0 && mac >= 0 && win >= 0);
     EXPECT_TRUE(lin != mac && mac != win && lin != win);
-    EXPECT_TRUE(rel.assets[lin].name.find("linux-amd64.zip") != std::string::npos);
-    EXPECT_TRUE(rel.assets[mac].name.find("macos.zip") != std::string::npos);
-    EXPECT_TRUE(rel.assets[win].name.find("win64.zip") != std::string::npos);
+    // Guard the index reads (select*Asset returns -1 on no match; EXPECT_TRUE doesn't abort here) so a
+    // fixture/parser regression reports the failed EXPECT above instead of an OOB rel.assets[-1] crash.
+    if (lin >= 0) EXPECT_TRUE(rel.assets[lin].name.find("linux-amd64.zip") != std::string::npos);
+    if (mac >= 0) EXPECT_TRUE(rel.assets[mac].name.find("macos.zip") != std::string::npos);
+    if (win >= 0) EXPECT_TRUE(rel.assets[win].name.find("win64.zip") != std::string::npos);
     // Wrong/foreign tokens (e.g. the miner's naming) must NOT match the daemon archives.
     EXPECT_EQ(selectDaemonAsset(rel, "linux-x64"), -1);
     EXPECT_EQ(selectDaemonAsset(rel, "linux-arm64"), -1);