#VU104935 Memory leak in Linux kernel - CVE-2025-21739

Vulnerability identifier: #VU104935

Vulnerability risk: Low

CVSSv4.0: 4.3 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2025-21739

CWE-ID: CWE-401

Exploitation vector: Local

Exploit availability: No

Vulnerable software:
Linux kernel
Operating systems & Components / Operating system

Vendor: Linux Foundation

Description

The vulnerability allows a local user to perform a denial of service (DoS) attack.

The vulnerability exists due to memory leak within the ufshcd_pltfrm_init() and ufshcd_pltfrm_remove() functions in drivers/ufs/host/ufshcd-pltfrm.c, within the ufshcd_pci_remove() and ufshcd_pci_probe() functions in drivers/ufs/host/ufshcd-pci.c, within the EXPORT_SYMBOL_GPL(), ufshcd_set_dma_mask() and ufshcd_alloc_host() functions in drivers/ufs/core/ufshcd.c. A local user can perform a denial of service (DoS) attack.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Linux kernel: All versions

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External links
https://git.kernel.org/stable/c/0c77c0d754fe83cb154715fcfec6c3faef94f207
https://git.kernel.org/stable/c/9c185beae09a3eb85f54777edafa227f7e03075d
https://git.kernel.org/stable/c/f8fb2403ddebb5eea0033d90d9daae4c88749ada

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Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.