CVE-2017-5443 Memory corruption in Firefox

What is CVE-2017-5443?

CVE-2017-5443 is a critical memory corruption vulnerability in Debian Debian Linux, published on 11 Jun 2018. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

An out-of-bounds write vulnerability while decoding improperly formed BinHex format archives. This vulnerability affects Thunderbird < 52.1, Firefox ESR < 45.9, Firefox ESR < 52.1, and Firefox < 53.

Weakness: CWE-787

Which versions are affected by CVE-2017-5443?

It affects 9 products.

Products include Debian Debian Linux, Mozilla Firefox, Mozilla Thunderbird, Redhat Enterprise Linux, Redhat Enterprise Linux Desktop, Redhat Enterprise Linux Server and 3 more.

How do I fix CVE-2017-5443?

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-2017-5443 being exploited?

There is no known exploitation of CVE-2017-5443 in the wild and no public exploit code.

Other vulnerabilities in Debian Debian Linux

• CVE-2015-3306 ProFTPD Improper Access Control Exploited Critical 10.0
• CVE-2025-49113 RoundCube Webmail Deserialization of Untrusted Data Exploited Critical 9.9
• CVE-2026-24061 GNU InetUtils Argument Injection Exploited Critical 9.8
• 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 DEBIAN-CVE-2017-5443, GHSA-6cvj-hx37-fq45, UBUNTU-CVE-2017-5443.