diff --git a/pkgs/development/libraries/ffmpeg/3.4.nix b/pkgs/development/libraries/ffmpeg/3.4.nix
index a5140fa01ca0..25c0a12f731a 100644
--- a/pkgs/development/libraries/ffmpeg/3.4.nix
+++ b/pkgs/development/libraries/ffmpeg/3.4.nix
@@ -9,4 +9,7 @@ callPackage ./generic.nix (rec {
   branch = "3.4.8";
   sha256 = "1d0r4yja2dkkyhdwx1migq46gsrcbajiv66263a5sq5bfr9dqkch";
   darwinFrameworks = [ Cocoa CoreMedia ];
+  knownVulnerabilities = [
+    "CVE-2021-30123"
+  ];
 } // args)