Arm Mali Graphics Processing Unit (GPU): memory corruption flaw under attack

What is affected

Arm Mali Graphics Processing Unit (GPU) is mostly run by companies, schools and public bodies, not on home computers. You are unlikely to have it yourself, but organisations that hold your data may. Breaches that start with flaws like this one are how personal data ends up leaked.

Arm Mali GPU Kernel Driver contains a use-after-free vulnerability that may allow a non-privileged user to gain root privilege and/or disclose information.

What an attacker can do

This is a memory corruption flaw. It lets an attacker corrupt the program's memory by feeding it specially crafted content: a web page, a file or a network message. The result ranges from a crash to the attacker running their own code.

How it is reached

Over the internet or network

Access the attacker needs

A basic user account

Does the victim have to do something?

No, works without the victim doing anything

What to do

1. At home: nothing to install. Keep your own devices updated and use a different password for every service, so that a breach at one organisation does not open your other accounts.
2. If you administer Arm Mali Graphics Processing Unit (GPU) at work: apply the vendor's fix or mitigation now and review logs for signs of compromise, because the flaw was being exploited before it was listed.
3. If the product is past its support date and no fix exists, take it off the internet or retire it.

Apply updates per vendor instructions or discontinue use of the product if updates are unavailable.

Vendor advisories and fixes

• developer.arm.comdeveloper.arm.com/Arm%20Security%20Center/Mali%20GPU%20Driver%20Vulnerabilities

How urgent is it

CISA added this vulnerability to its Known Exploited Vulnerabilities catalogue on July 7, 2023, which means there is reliable evidence of attacks in the wild. US federal agencies must fix it by July 28, 2023, a deadline that has already passed. That deadline does not bind anyone else, but it shows how seriously the agency rates it.

The EPSS model estimates a 3.0% probability that this flaw will be exploited somewhere in the next 30 days. That is higher than 87% of all scored vulnerabilities.

Its CVSS severity score is 8.8 out of 10 (high), as recorded in the US National Vulnerability Database.

Technical description

. The Arm Mali GPU kernel driver allows an unprivileged user to achieve access to freed memory, leading to information disclosure or root privilege escalation. This affects Bifrost r16p0 through r29p0 before r30p0, Valhall r19p0 through r29p0 before r30p0, and Midgard r28p0 through r30p0.