diff --git a/src/patch/parse.rs b/src/patch/parse.rs
index 0191542..793ae31 100644
--- a/src/patch/parse.rs
+++ b/src/patch/parse.rs
@@ -273,7 +273,7 @@ fn hunk_header<T: Text + ?Sized>(input: &T) -> Result<(HunkRange, HunkRange, Opt
 }
 
 fn range<T: Text + ?Sized>(s: &T) -> Result<HunkRange> {
-    let (start, len) = if let Some((start, len)) = s.split_at_exclusive(",") {
+    let (start, len): (usize, usize) = if let Some((start, len)) = s.split_at_exclusive(",") {
         (
             start.parse().ok_or(ParsePatchErrorKind::InvalidRange)?,
             len.parse().ok_or(ParsePatchErrorKind::InvalidRange)?,
@@ -282,6 +282,11 @@ fn range<T: Text + ?Sized>(s: &T) -> Result<HunkRange> {
         (s.parse().ok_or(ParsePatchErrorKind::InvalidRange)?, 1)
     };
 
+    // reject ranges that overflow
+    start
+        .checked_add(len)
+        .ok_or(ParsePatchErrorKind::InvalidRange)?;
+
     Ok(HunkRange::new(start, len))
 }
 
diff --git a/src/patch/tests.rs b/src/patch/tests.rs
index 7adc0a8..9efa79a 100644
--- a/src/patch/tests.rs
+++ b/src/patch/tests.rs
@@ -638,6 +638,24 @@ fn non_utf8_escaped_filename_returns_error_on_str_parse() {
     );
 }
 
+#[test]
+fn hunk_range_overflow() {
+    let s = format!(
+        "\
+--- a/file.txt
++++ b/file.txt
+@@ -{},1 +1 @@
+-old
++new
+",
+        usize::MAX,
+    );
+    assert_eq!(
+        crate::Patch::from_str(&s).unwrap_err().kind,
+        ParsePatchErrorKind::InvalidRange,
+    );
+}
+
 mod error_display {
     use alloc::string::ToString;