diff --git a/aries-backchannels/acapy/requirements-master.txt b/aries-backchannels/acapy/requirements-master.txt
index 4d77a4f1..6a379f3c 100644
--- a/aries-backchannels/acapy/requirements-master.txt
+++ b/aries-backchannels/acapy/requirements-master.txt
@@ -1 +1,2 @@
-aries-cloudagent[indy]@git+https://github.com/hyperledger/aries-cloudagent-python@master
\ No newline at end of file
+aries-cloudagent[indy]@git+https://github.com/hyperledger/aries-cloudagent-python@master
+zipp>=3.19.1 # not directly required, pinned by Snyk to avoid a vulnerability
\ No newline at end of file