Debian 9 DLA-2588-1 Critical: Zeromq3 Memory Leak And Heap Overflow

CVE-2021-20234

Memory leak in client induced by malicious server(s) without CURVE/ZAP.

From issue description [1].
When a pipe processes a delimiter and is already not in active state but
still has an unfinished message, the message is leaked.

CVE-2021-20235

Heap overflow when receiving malformed ZMTP v1 packets.

From issue description [2].
The static allocator was implemented to shrink its recorded size similarly
to the shared allocator. But it does not need to, and it should not,
because unlike the shared one the static allocator always uses a static
buffer, with a size defined by the ZMQ_IN_BATCH_SIZE socket option
(default 8192), so changing the size opens the library to heap overflows.
The static allocator is used only with ZMTP v1 peers.

[1] https://github.com/zeromq/libzmq/security/advisories/GHSA-wfr2-29gj-5w87
[2] https://github.com/zeromq/libzmq/security/advisories/GHSA-fc3w-qxf5-7hp6