Log in Start free

Vulnerability · Published Oct 21, 2024 · Assigned by Linux

CVE-2024-49854block, bfq: fix uaf for accessing waker_bfqq after splitting

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 0.2% (higher than 12% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)7.8High
Exploit odds (30 days)0.2%top 88.0% 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: block, bfq: fix uaf for accessing waker_bfqq after splitting After commit 42c306ed7233 ("block, bfq: don't break merge chain in bfq_split_bfqq()"), if the current procress is the last holder of bfqq, the bfqq can be freed after bfq_split_bfqq(). Hence recored the bfqq and then access bfqq->waker_bfqq may trigger UAF. What's more, the waker_bfqq may in the merge chain of bfqq, hence just recored waker_bfqq is still not safe. Fix the problem by adding a helper bfq_waker_bfqq() to check if bfqq->waker_bfqq is in the merge chain, and current procress is the only holder.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
Debian:12linux6.1.115-1DEBIAN-CVE-2024-49854
Debian:13linux6.11.2-1DEBIAN-CVE-2024-49854
Debian:14linux6.11.2-1DEBIAN-CVE-2024-49854
Ubuntu:22.04:LTSlinux-allwinner-5.19no fix listedUBUNTU-CVE-2024-49854
Ubuntu:22.04:LTSlinux-aws-5.19no fix listedUBUNTU-CVE-2024-49854
Ubuntu:22.04:LTSlinux-aws-6.2no fix listedUBUNTU-CVE-2024-49854
Ubuntu:22.04:LTSlinux-aws-6.5no fix listedUBUNTU-CVE-2024-49854
Ubuntu:22.04:LTSlinux-azure-5.19no fix listedUBUNTU-CVE-2024-49854
Ubuntu:22.04:LTSlinux-azure-6.2no fix listedUBUNTU-CVE-2024-49854
Ubuntu:22.04:LTSlinux-azure-6.5no fix listedUBUNTU-CVE-2024-49854
Ubuntu:22.04:LTSlinux-azure-fde-5.19no fix listedUBUNTU-CVE-2024-49854
Ubuntu:22.04:LTSlinux-azure-fde-6.2no fix listedUBUNTU-CVE-2024-49854
Ubuntu:22.04:LTSlinux-gcp-5.19no fix listedUBUNTU-CVE-2024-49854
Ubuntu:22.04:LTSlinux-gcp-6.2no fix listedUBUNTU-CVE-2024-49854
Ubuntu:22.04:LTSlinux-gcp-6.5no fix listedUBUNTU-CVE-2024-49854
Ubuntu:22.04:LTSlinux-hwe-5.19no fix listedUBUNTU-CVE-2024-49854
Ubuntu:22.04:LTSlinux-hwe-6.2no fix listedUBUNTU-CVE-2024-49854
Ubuntu:22.04:LTSlinux-hwe-6.5no fix listedUBUNTU-CVE-2024-49854
Ubuntu:22.04:LTSlinux-intel-iot-realtimeno fix listedUBUNTU-CVE-2024-49854
Ubuntu:22.04:LTSlinux-lowlatency-hwe-5.19no fix listedUBUNTU-CVE-2024-49854
Ubuntu:22.04:LTSlinux-lowlatency-hwe-6.2no fix listedUBUNTU-CVE-2024-49854
Ubuntu:22.04:LTSlinux-lowlatency-hwe-6.5no fix listedUBUNTU-CVE-2024-49854
Ubuntu:22.04:LTSlinux-nvidia-6.2no fix listedUBUNTU-CVE-2024-49854
Ubuntu:22.04:LTSlinux-nvidia-6.5no fix listedUBUNTU-CVE-2024-49854
Ubuntu:22.04:LTSlinux-oem-5.17no fix listedUBUNTU-CVE-2024-49854
Ubuntu:22.04:LTSlinux-oem-6.0no fix listedUBUNTU-CVE-2024-49854
Ubuntu:22.04:LTSlinux-oem-6.1no fix listedUBUNTU-CVE-2024-49854
Ubuntu:22.04:LTSlinux-oem-6.5no fix listedUBUNTU-CVE-2024-49854
Ubuntu:22.04:LTSlinux-oracle-6.5no fix listedUBUNTU-CVE-2024-49854
Ubuntu:24.04:LTSlinux-raspi-realtimeno fix listedUBUNTU-CVE-2024-49854
Ubuntu:22.04:LTSlinux-realtimeno fix listedUBUNTU-CVE-2024-49854
Ubuntu:22.04:LTSlinux-riscvno fix listedUBUNTU-CVE-2024-49854
Ubuntu:22.04:LTSlinux-riscv-5.19no fix listedUBUNTU-CVE-2024-49854
Ubuntu:22.04:LTSlinux-riscv-6.5no fix listedUBUNTU-CVE-2024-49854
Ubuntu:22.04:LTSlinux-starfive-5.19no fix listedUBUNTU-CVE-2024-49854
Ubuntu:22.04:LTSlinux-starfive-6.2no fix listedUBUNTU-CVE-2024-49854
Ubuntu:22.04:LTSlinux-starfive-6.5no fix listedUBUNTU-CVE-2024-49854

Affected products (as reported)

VendorProductVersions
Linux Linux e0c20d88b7dce85d2703bb6ba77bf359959675cd – before 63a07379fdb6c72450cb05294461c6016b8b7726de6c5e3a456019d2182e345730e59721714fa0b5 – before de0456460f2abf921e356ed2bd8da87a376680bd19f3bec2ac4be329b9bd12b18a989b867618d2d8 – before 0780451f03bf518bc032a7c584de8f92e2d39d7f13b3d0e8cb121f99b11918a0d4bcc1ce4647d352 – before 0b8bda0ff17156cd3f60944527c9d8c9f99f15834780f50ea50cfe8e89fc3747bf3dd155488433bb – before cae58d19121a70329cf971359e2518c93fec04fe42c306ed723321af4003b2a41bb73728cab54f85 – before 1ba0403ac6447f2d63914fb760c44a3b19c44eaf9e813033594b141f61ff0ef0cfaaef292564b0413a5f45a4ad4e1fd36b0a998eef03d76a4f02a2a8
Linux Linux see references

References