CVE Catalog

CVE-2024-39496

HighCVSS 7.8
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.29%

21th percentile - higher than 21% of all known CVEs

Summary

In the Linux kernel, the btrfs filesystem has a use-after-free vulnerability caused by a race during device replace. While loading zone info, a device is extracted from the chunk map without proper synchronization, which can lead to use of freed memory after the replace operation completes.

Risk Assessment

An attacker could exploit this vulnerability to corrupt kernel memory, potentially leading to system crash or privilege escalation.

Recommendation

It is recommended to immediately update the Linux kernel to a version containing the fix that enlarges the critical section under the device replace rwsem protection.

Other vulnerabilities in Linux kernel

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Original NVD description (English source)

In the Linux kernel, the following vulnerability has been resolved: btrfs: zoned: fix use-after-free due to race with dev replace While loading a zone's info during creation of a block group, we can race with a device replace operation and then trigger a use-after-free on the device that was just replaced (source device of the replace operation). This happens because at btrfs_load_zone_info() we extract a device from the chunk map into a local variable and then use the device while not under the protection of the device replace rwsem. So if there's a device replace operation happening when we extract the device and that device is the source of the replace operation, we will trigger a use-after-free if before we finish using the device the replace operation finishes and frees the device. Fix this by enlarging the critical section under the protection of the device replace rwsem so that all uses of the device are done inside the critical section.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS