Affected: IBM Qiskit SDK

Qiskit SDK 0.45.0 through 1.2.4 could allow a remote attacker to cause a denial of service using a maliciously crafted QPY file containing a malformed symengine serialization stream which can cause a segfault within the symengine library.

Affected: PyPI: qiskit, PyPI: qiskit-terra

### Impact

A maliciously crafted QPY file containing a malformed `symengine` serialization stream as part of the larger QPY serialization of a `ParameterExpression` object can cause a segfault within the `symengine` library, allowing an attacker to terminate the hosting process deserializing the QPY payload.

### Patches

This issue is addressed in 1.3.0 when using QPY format version 13. QPY format versions 10, 11, and 12 are all still inherently vulnerable if they are using symengine symbolic encoding and `symengine <= 0.13.0` is installed in the deserializing environment (as of publishing there is no newer compatible release of symengine available). Using QPY 13 is strongly recommended for this reason.

The symengine 0.14.0 release has addressed the segfault issue, but it is backward incompatible and will not work with any Qiskit release; it also prevents loading a payload generated with any other version of symengine. Using QPY 13 is strongly recommended for this reason.

It is also strongly suggested to patch the locally installed version of symengine in the deserializing environment to prevent the specific segfault. The commit [1] can be applied on top of symengine 0.13.0 and used to build a patched python library that will not segfault in the presence of a malformed payload and instead raise a `RuntimeError` which will address the vulnerability.

### Workarounds

As QPY is backwards compatible `qiskit.qpy.load()` function will always attempt to deserialize the `symeng…