diff --git a/pkgs/development/interpreters/spidermonkey/38.nix b/pkgs/development/interpreters/spidermonkey/38.nix
index d2aabfe64d9a..22ce5a0b387c 100644
--- a/pkgs/development/interpreters/spidermonkey/38.nix
+++ b/pkgs/development/interpreters/spidermonkey/38.nix
@@ -67,5 +67,6 @@ stdenv.mkDerivation rec {
 
     maintainers = [ maintainers.abbradar ];
     platforms = platforms.unix;
+    knownVulnerabilities = [ "SpiderMonkey 38 is outdated and contains known security vulnerabilities." ]; # as per https://developer.mozilla.org/en-US/docs/Mozilla/Projects/SpiderMonkey/Releases/38
   };
 }