diff --git a/action.yml b/action.yml
index 471b2d9..373373f 100644
--- a/action.yml
+++ b/action.yml
@@ -273,7 +273,7 @@ runs:
               BEGIN { printing=0 }
               /^## / {
                 if (printing) exit
-                if (index($0, ver) > 0) { printing=1; next }
+                if ($0 ~ "^## " ver "[ (]") { printing=1; next }
               }
               printing { print }
             ' "$changelog_file")
diff --git a/src/ecosystems/rust.rs b/src/ecosystems/rust.rs
index f7a5baf..8b7152f 100644
--- a/src/ecosystems/rust.rs
+++ b/src/ecosystems/rust.rs
@@ -236,7 +236,8 @@ impl RustAdapter {
             let candidate = current.join("Cargo.toml");
             if candidate.exists() && candidate != manifest_path {
                 let content = std::fs::read_to_string(&candidate)?;
-                if content.contains("[workspace]") {
+                let doc: DocumentMut = content.parse()?;
+                if doc.get("workspace").is_some() {
                     return Ok(current);
                 }
             }