OSV-2020-784 Bad-cast to zmq::session_base_t from invalid vptr
A bad cast from an invalid virtual pointer in ZeroMQ can cause a crash, leading to denial of service for applications using the library.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is OSV-2020-784?
OSV-2020-784 is a memory corruption vulnerability in libzmq, published on 14 Jul 2020. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
OSS-Fuzz report: https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=24018
Crash type: Bad-cast
Crash state:
Bad-cast to zmq::session_base_t from invalid vptr
zmq::stream_engine_base_t::in_event_internal
zmq::stream_engine_base_t::in_event
Which versions are affected by OSV-2020-784?
1 open source package ship an affected version, including libzmq.
| Package | Affected | Fixed in |
|---|---|---|
libzmq OSS-Fuzz | All versions | None |
How do I fix OSV-2020-784?
No fix has been published for OSV-2020-784 yet. Limit exposure of the affected software until one is available.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is OSV-2020-784 being exploited?
There is no known exploitation of OSV-2020-784 in the wild and no public exploit code.