CyberSecBulletin
CVE-2022-38181Exploited in the wildNVD status: Analyzed

Arm Mali GPU Kernel Driver Use-After-Free

Published Updated By the CyberSecBulletin desk

CVE-2022-38181 is a high-severity use after free vulnerability in Bifrost GPU Kernel Driver from Arm, with a CVSS 3.1 base score of 8.8 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, without any action from a user. Affected Bifrost GPU Kernel Driver versions: r0p0 through r38p1; r39p0. The record does not name a fixed version, so check the vendor advisory. CISA added it to the Known Exploited Vulnerabilities catalogue on March 30, 2023, which means attacks have been observed in the wild.

Patch now

Attackers are already exploiting this vulnerability, according to CISA.

What to do

  1. Check which version of Bifrost GPU Kernel Driver you run against the affected versions below, and install the vendor's latest release.
  2. CISA's required action: Apply updates per vendor instructions.
  3. Read the advisory on developer.arm.com for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
ArmBifrost GPU Kernel Driverr0p0 through r38p1; r39p0Not stated
ArmMidgard GPU Kernel Driverr4p0 through r31p0Not stated
ArmValhall GPU Kernel Driverr19p0 through r38p1; r39p0Not stated

Version data comes from NVD's product matching. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
LowA basic user account is enough.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.18.8HighNVD
CVSS 3.18.8HighCISA (ADP)

Official description

The Arm Mali GPU kernel driver allows unprivileged users to access freed memory because GPU memory operations are mishandled. This affects Bifrost r0p0 through r38p1, and r39p0; Valhall r19p0 through r38p1, and r39p0; and Midgard r4p0 through r32p0.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Use After Free

The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory belongs to the code that operates on the new pointer.

How developers prevent this class of flaw

  • Choose a language that provides automatic memory management.
  • When freeing pointers, be sure to set them to NULL once they are freed. However, the utilization of multiple or complex data structures may lower the usefulness of this strategy.

More Use After Free vulnerabilities (CWE-416)

Timeline

  1. CVE record published.
  2. Added to CISA's Known Exploited Vulnerabilities catalogue.
  3. Deadline for US federal agencies to remediate, set by CISA.
  4. CISA published its SSVC assessment (exploitation: active, automatable: no, technical impact: total).
  5. Record last changed materially (score, affected products, status or references).

References

Technical write-ups (may include proof of concept)

Other vulnerabilities in Bifrost GPU Kernel Driver

All Bifrost GPU Kernel Driver vulnerabilities

Recent Use After Free vulnerabilities

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