CVE-2020-15656 Memory corruption in Firefox

What is CVE-2020-15656?

CVE-2020-15656 is a high-severity memory corruption vulnerability in Canonical Ubuntu Linux, published on 10 Aug 2020. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

Official description

JIT optimizations involving the Javascript arguments object could confuse later optimizations. This risk was already mitigated by various precautions in the code, resulting in this bug rated at only moderate severity. This vulnerability affects Firefox ESR < 78.1, Firefox < 79, and Thunderbird < 78.1.

Weakness: CWE-843

Which versions are affected by CVE-2020-15656?

It affects 5 products.

Products include Canonical Ubuntu Linux, Mozilla Firefox, Mozilla Firefox Esr, Mozilla Thunderbird, Opensuse Leap.

How do I fix CVE-2020-15656?

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-2020-15656 being exploited?

There is no known exploitation of CVE-2020-15656 in the wild and no public exploit code.

Other vulnerabilities in Canonical Ubuntu Linux

• CVE-2020-11651 SaltStack Salt Authentication Bypass Exploited Critical 9.8
• CVE-2020-7247 OpenSMTPD Remote Code Execution Exploited Critical 9.8
• CVE-2019-16928 Exim Out-of-bounds Write Exploited Critical 9.8
• CVE-2018-6789 Exim Buffer Overflow Exploited Critical 9.8
• CVE-2015-2590 Oracle Java SE and Java SE Embedded Remote Code Execution Exploited Critical 9.8

All Canonical Ubuntu Linux vulnerabilities

Sources

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

Also known as GHSA-cwww-4cwr-37ph, UBUNTU-CVE-2020-15656.