Log in Start free

Vulnerability · Published May 21, 2024 · Assigned by Linux

CVE-2021-47334misc/libmasm/module: Fix two use after free in ibmasm_init_one

High 7.8

In plain English

A high-severity security flaw in Linux from Linux. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 20% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS NVD)7.8High
Exploit odds (30 days)0.3%top 79.7% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known

Official description

In the Linux kernel, the following vulnerability has been resolved: misc/libmasm/module: Fix two use after free in ibmasm_init_one In ibmasm_init_one, it calls ibmasm_init_remote_input_dev(). Inside ibmasm_init_remote_input_dev, mouse_dev and keybd_dev are allocated by input_allocate_device(), and assigned to sp->remote.mouse_dev and sp->remote.keybd_dev respectively. In the err_free_devices error branch of ibmasm_init_one, mouse_dev and keybd_dev are freed by input_free_device(), and return error. Then the execution runs into error_send_message error branch of ibmasm_init_one, where ibmasm_free_remote_input_dev(sp) is called to unregister the freed sp->remote.mouse_dev and sp->remote.keybd_dev. My patch add a "error_init_remote" label to handle the error of ibmasm_init_remote_input_dev(), to avoid the uaf bugs.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
Debian:12linux5.14.6-1DEBIAN-CVE-2021-47334
Debian:13linux5.14.6-1DEBIAN-CVE-2021-47334
Debian:14linux5.14.6-1DEBIAN-CVE-2021-47334
Ubuntu:22.04:LTSlinux-allwinner-5.19no fix listedUBUNTU-CVE-2021-47334
Ubuntu:22.04:LTSlinux-aws-5.19no fix listedUBUNTU-CVE-2021-47334
Ubuntu:22.04:LTSlinux-aws-6.2no fix listedUBUNTU-CVE-2021-47334
Ubuntu:22.04:LTSlinux-azure-5.19no fix listedUBUNTU-CVE-2021-47334
Ubuntu:22.04:LTSlinux-azure-6.2no fix listedUBUNTU-CVE-2021-47334
Ubuntu:22.04:LTSlinux-azure-fde-5.19no fix listedUBUNTU-CVE-2021-47334
Ubuntu:22.04:LTSlinux-azure-fde-6.2no fix listedUBUNTU-CVE-2021-47334
Ubuntu:22.04:LTSlinux-gcp-5.19no fix listedUBUNTU-CVE-2021-47334
Ubuntu:22.04:LTSlinux-gcp-6.2no fix listedUBUNTU-CVE-2021-47334
Ubuntu:22.04:LTSlinux-hwe-5.19no fix listedUBUNTU-CVE-2021-47334
Ubuntu:22.04:LTSlinux-hwe-6.2no fix listedUBUNTU-CVE-2021-47334
Ubuntu:22.04:LTSlinux-intel-iot-realtimeno fix listedUBUNTU-CVE-2021-47334
Ubuntu:22.04:LTSlinux-lowlatency-hwe-5.19no fix listedUBUNTU-CVE-2021-47334
Ubuntu:22.04:LTSlinux-lowlatency-hwe-6.2no fix listedUBUNTU-CVE-2021-47334
Ubuntu:22.04:LTSlinux-nvidia-6.2no fix listedUBUNTU-CVE-2021-47334
Ubuntu:22.04:LTSlinux-oem-5.17no fix listedUBUNTU-CVE-2021-47334
Ubuntu:22.04:LTSlinux-oem-6.0no fix listedUBUNTU-CVE-2021-47334
Ubuntu:22.04:LTSlinux-oem-6.1no fix listedUBUNTU-CVE-2021-47334
Ubuntu:24.04:LTSlinux-raspi-realtimeno fix listedUBUNTU-CVE-2021-47334
Ubuntu:22.04:LTSlinux-realtimeno fix listedUBUNTU-CVE-2021-47334
Ubuntu:22.04:LTSlinux-riscvno fix listedUBUNTU-CVE-2021-47334
Ubuntu:22.04:LTSlinux-riscv-5.19no fix listedUBUNTU-CVE-2021-47334
Ubuntu:22.04:LTSlinux-starfive-5.19no fix listedUBUNTU-CVE-2021-47334
Ubuntu:22.04:LTSlinux-starfive-6.2no fix listedUBUNTU-CVE-2021-47334

Affected products (as reported)

VendorProductVersions
Linux Linux 736ce43295682d060f2b93624b4a339f9af6aab1 – before 1512e7dc5eb08b7d92a12e2bfcd9cb8c4a1ec069736ce43295682d060f2b93624b4a339f9af6aab1 – before 29ba8e2ba89ee2862a26d91204dd5fe77ceee25a736ce43295682d060f2b93624b4a339f9af6aab1 – before 5b06ca113bf197aab2ab61288f42506e0049fbab736ce43295682d060f2b93624b4a339f9af6aab1 – before 481a76d4749ee3a27f902ba213fdcbb4bb39720e736ce43295682d060f2b93624b4a339f9af6aab1 – before 38660031e80eaa6cc9370b031c180612f414b00d736ce43295682d060f2b93624b4a339f9af6aab1 – before b9c87ce3bc6331f82811a8cf8e930423c22523a3736ce43295682d060f2b93624b4a339f9af6aab1 – before ef1067d2baa847d53c9988510d99fb494de4d12c736ce43295682d060f2b93624b4a339f9af6aab1 – before a7268e8a227d5a4f0bd1584f556246b0224ab274
Linux Linux 2.6.16

References