Impact
A security vulnerability has been identified in mailcow affecting versions < 2024-01c. This vulnerability potentially allows attackers on the same subnet to connect to exposed ports of a Docker container, even when the port is bound to 127.0.0.1.
The vulnerability has been addressed by implementing additional iptables/nftables rules. These rules drop packets for Docker containers on ports 3306, 6379, 8983, and 12345, where the input interface is not br-mailcow and the output interface is br-mailcow.
It is highly recommended that all users upgrade to this latest version to ensure the security of their systems.
Patches
Versions including 2024-01c and later
Workarounds
Users who are unable to update immediately can apply the following iptables/nftables rule:
iptables:
iptables -I DOCKER-USER ! -i br-mailcow -o br-mailcow -p tcp -m multiport --dport 3306,6379,8983,12345 -j DROP
nftables:
nft insert rule ip "filter" "DOCKER-USER" iifname != "br-mailcow" oifname "br-mailcow" tcp dport {3306, 6379, 8983, 12345} counter packets 0 bytes 0 drop
killerbees19 Analyst
Impact
A security vulnerability has been identified in mailcow affecting versions < 2024-01c. This vulnerability potentially allows attackers on the same subnet to connect to exposed ports of a Docker container, even when the port is bound to 127.0.0.1.
The vulnerability has been addressed by implementing additional iptables/nftables rules. These rules drop packets for Docker containers on ports 3306, 6379, 8983, and 12345, where the input interface is not
br-mailcowand the output interface isbr-mailcow.It is highly recommended that all users upgrade to this latest version to ensure the security of their systems.
Patches
Versions including 2024-01c and later
Workarounds
Users who are unable to update immediately can apply the following iptables/nftables rule:
iptables:
iptables -I DOCKER-USER ! -i br-mailcow -o br-mailcow -p tcp -m multiport --dport 3306,6379,8983,12345 -j DROPnftables:
nft insert rule ip "filter" "DOCKER-USER" iifname != "br-mailcow" oifname "br-mailcow" tcp dport {3306, 6379, 8983, 12345} counter packets 0 bytes 0 drop