Fix potential segfault (backport #884)

[mergify]

This is an automatic backport of pull request #884 done by Mergify.
Cherry-pick of ebc56f8 has failed:

On branch mergify/bp/openvas-20.08/pr-884
Your branch is ahead of 'origin/openvas-20.08' by 1 commit.
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You are currently cherry-picking commit ebc56f8d.
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	both modified:   CHANGELOG.md

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To fix up this pull request, you can check it out locally. See documentation: https://docs.github.com/en/github/collaborating-with-pull-requests/reviewing-changes-in-pull-requests/checking-out-pull-requests-locally

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