#VU105675 Memory leak in Linux kernel - CVE-2025-21864
Vulnerability identifier: #VU105675
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:
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 tcp_add_backlog() function in net/ipv4/tcp_ipv4.c, within the tcp_ofo_queue(), tcp_queue_rcv(), tcp_data_queue() and tcp_rcv_established() functions in net/ipv4/tcp_input.c, within the tcp_fastopen_add_skb() function in net/ipv4/tcp_fastopen.c. A local user can perform a denial of service (DoS) attack.
Mitigation
Install update from vendor's website.
Vulnerable software versions
Linux kernel: 6.6, 6.6 rc1, 6.6 rc2, 6.6 rc3, 6.6 rc4, 6.6 rc5, 6.6 rc6, 6.6.1, 6.6.2, 6.6.3, 6.6.4, 6.6.5, 6.6.6, 6.6.7, 6.6.8, 6.6.9, 6.6.10, 6.6.11, 6.6.12, 6.6.13, 6.6.14, 6.6.15, 6.6.16, 6.6.17, 6.6.18, 6.6.19, 6.6.20, 6.6.21, 6.6.22, 6.6.23, 6.6.24, 6.6.25, 6.6.26, 6.6.27, 6.6.28, 6.6.29, 6.6.30, 6.6.31, 6.6.32, 6.6.33, 6.6.34, 6.6.35, 6.6.36, 6.6.37, 6.6.38, 6.6.39, 6.6.40, 6.6.41, 6.6.42, 6.6.43, 6.6.44, 6.6.45, 6.6.46, 6.6.47, 6.6.48, 6.6.49, 6.6.50, 6.6.51, 6.6.52, 6.6.53, 6.6.54, 6.6.55, 6.6.56, 6.6.57, 6.6.58, 6.6.59, 6.6.60, 6.6.61, 6.6.62, 6.6.63, 6.6.64, 6.6.65, 6.6.66, 6.6.67, 6.6.68, 6.6.69, 6.6.70, 6.6.71, 6.6.72, 6.6.73, 6.6.74, 6.6.75, 6.6.76, 6.6.77, 6.6.78, 6.6.79
External links
https://git.kernel.org/stable/c/69cafd9413084cd5012cf5d7c7ec6f3d493726d9
https://git.kernel.org/stable/c/87858bbf21da239ace300d61dd209907995c0491
https://git.kernel.org/stable/c/9b6412e6979f6f9e0632075f8f008937b5cd4efd
https://git.kernel.org/stable/c/cd34a07f744451e2ecf9005bb7d24d0b2fb83656
https://git.kernel.org/stable/c/f1d5e6a5e468308af7759cf5276779d3155c5e98
https://mirrors.edge.kernel.org/pub/linux/kernel/v6.x/ChangeLog-6.6.80
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.
