CVE-2020-36430 Memory corruption in n/a

High 7.8 Published 20 Jul 2021 Updated 4 Aug 2024

A heap-based buffer overflow in libass allows attackers to execute arbitrary code or cause denial of service via crafted font data.

Exploited in the wild: Not known
Login needed: Not needed
Attackable: Local or same network only
Victim action needed: A user has to click or open something
Fix: Available

What is CVE-2020-36430?

CVE-2020-36430 is a high-severity memory corruption vulnerability in Fedoraproject Fedora, published on 20 Jul 2021. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.

Official description

libass 0.15.x before 0.15.1 has a heap-based buffer overflow in decode_chars (called from decode_font and process_text) because the wrong integer data type is used for subtraction.

Weakness: CWE-787

Which versions are affected by CVE-2020-36430?

It affects 2 products.

Linux distribution packages (17)

`libass` SUSE:Enterprise Storage 6	All versions	`0.14.0-3.9.1`
`libass` SUSE:Linux Enterprise High Performance Computing 15 SP1-ESPOS	All versions	`0.14.0-3.9.1`
`libass` SUSE:Linux Enterprise High Performance Computing 15 SP1-LTSS	All versions	`0.14.0-3.9.1`
`libass` SUSE:Linux Enterprise High Performance Computing 15-ESPOS	All versions	`0.14.0-3.9.1`
`libass` SUSE:Linux Enterprise High Performance Computing 15-LTSS	All versions	`0.14.0-3.9.1`
`libass` SUSE:Linux Enterprise Module for Desktop Applications 15 SP2	All versions	`0.14.0-3.9.1`
`libass` SUSE:Linux Enterprise Module for Desktop Applications 15 SP3	All versions	`0.14.0-3.9.1`
`libass` SUSE:Linux Enterprise Server 15 SP1-BCL	All versions	`0.14.0-3.9.1`
`libass` SUSE:Linux Enterprise Server 15 SP1-LTSS	All versions	`0.14.0-3.9.1`
`libass` SUSE:Linux Enterprise Server 15-LTSS	All versions	`0.14.0-3.9.1`
`libass` SUSE:Linux Enterprise Server for SAP Applications 15	All versions	`0.14.0-3.9.1`
`libass` SUSE:Linux Enterprise Server for SAP Applications 15 SP1	All versions	`0.14.0-3.9.1`
`libass` SUSE:Manager Proxy 4.0	All versions	`0.14.0-3.9.1`
`libass` SUSE:Manager Retail Branch Server 4.0	All versions	`0.14.0-3.9.1`
`libass` SUSE:Manager Server 4.0	All versions	`0.14.0-3.9.1`
`libass` openSUSE:Leap 15.2	All versions	`0.14.0-lp152.4.9.1`
`libass` openSUSE:Leap 15.3	All versions	`0.14.0-3.9.1`

Products include Fedoraproject Fedora, Libass Project Libass.

How do I fix CVE-2020-36430?

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-2020-36430 being exploited?

There is no known exploitation of CVE-2020-36430 in the wild and no public exploit code.

All Fedoraproject Fedora vulnerabilities

Sources

Also known as DEBIAN-CVE-2020-36430, GHSA-pqvw-6c6x-gvwh, MGASA-2021-0413, OESA-2021-1303, SUSE-SU-2021:2792-1, openSUSE-SU-2021:1174-1 and 1 more.