diff --git a/deny.toml b/deny.toml
index 189043103..b32af0979 100644
--- a/deny.toml
+++ b/deny.toml
@@ -18,6 +18,11 @@ ignore = [
     # this should be fixed by upgrading to iroh 1.0 once it is released.
     "RUSTSEC-2025-0134",
 
+    # Unmaintained proc-macro-error2
+    # Transitive dependency of typescript-type-def 0.5.13.
+    # <https://rustsec.org/advisories/RUSTSEC-2026-0173>
+    "RUSTSEC-2026-0173",
+
     # rustls-webpki v0.102.8
     # We cannot upgrade to >=0.103.10 because
     # it is a transitive dependency of iroh 0.35.0