CVE-2017-12178 Memory corruption in xorg-x11-server

What is CVE-2017-12178?

CVE-2017-12178 is a critical memory corruption vulnerability in Debian Debian Linux, published on 24 Jan 2018. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

xorg-x11-server before 1.19.5 had wrong extra length check in ProcXIChangeHierarchy function allowing malicious X client to cause X server to crash or possibly execute arbitrary code.

Weakness: CWE-20, CWE-391

Which versions are affected by CVE-2017-12178?

It affects 2 products.

Products include Debian Debian Linux, X.org X Server.

How do I fix CVE-2017-12178?

Upgrade to a fixed version.

Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.

Is CVE-2017-12178 being exploited?

There is no known exploitation of CVE-2017-12178 in the wild and no public exploit code.

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• CVE-2025-39682 Linux Kernel Improper Check for Unusual or Exceptional Conditions Exploited Critical 9.8
• CVE-2024-9680 Mozilla Firefox Use-After-Free Exploited Critical 9.8

All Debian Debian Linux vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as ALPINE-CVE-2017-12178, DEBIAN-CVE-2017-12178, GHSA-7xv3-2rc8-75j5, UBUNTU-CVE-2017-12178.