diff --git a/src/locate/mod.rs b/src/locate/mod.rs
index 3eb399c..9041027 100644
--- a/src/locate/mod.rs
+++ b/src/locate/mod.rs
@@ -490,8 +490,10 @@ impl DbReader {
             return None;
         };
 
-        // drop nul byte when matching
-        match String::from_utf8_lossy(&buf[..buf.len() - 1]).as_ref() {
+        // drop the trailing nul byte when matching. `read_until` may stop at EOF
+        // without one (e.g. a too-short file), so strip it only if present rather
+        // than slicing `buf.len() - 1`, which underflows when `buf` is empty.
+        match String::from_utf8_lossy(buf.strip_suffix(b"\0").unwrap_or(&buf)).as_ref() {
             "LOCATE02" => Some(DbFormat::Locate02),
             _ => None,
         }
diff --git a/tests/db_tests.rs b/tests/db_tests.rs
index 89e949d..609071e 100644
--- a/tests/db_tests.rs
+++ b/tests/db_tests.rs
@@ -253,3 +253,16 @@ fn test_updatedb_locate_roundtrip() {
         "locate output did not contain the indexed file: {stdout:?}"
     );
 }
+
+#[test]
+fn test_locate_one_byte_db() {
+    let dir = tempfile::tempdir().unwrap();
+    let db = dir.path().join("db_1byte");
+    std::fs::write(&db, b"X").unwrap();
+    Command::cargo_bin("locate")
+        .expect("couldn't find locate binary")
+        .arg(format!("--database={}", db.display()))
+        .arg("foo")
+        .assert()
+        .code(1);
+}