Vulnerability identifier: #VU18813

Vulnerability risk: Medium

CVSSv3.1: 6.5 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2019-11477

CWE-ID: CWE-190

Exploitation vector: Network

Exploit availability: No

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

Vendor: Linux Foundation

Description

The vulnerability allows a remote attacker to perform denial of service (DoS) attack.

The vulnerability exists due to integer overflow when handling TCP Selective Acknowledgments (SACKs) due to incorrect processing of TCP_SKB_CB(skb)->tcp_gso_segs value in Linux kernel. A remote non-authenticated attacker can send specially crafted network traffic to the affected system, trigger integer overflow and render the system unavailable.

Successful exploitation of the vulnerability allows a remote attacker to perform denial of service (DoS) attack.

Mitigation

Update your kernel to the latest version.

Vulnerable software versions

Linux kernel: 4.19 - 4.19.51, 4.14 - 4.14.126, 4.9 - 4.9.181, 4.4.0 - 4.4.181, 5.0 - 5.0.21, 5.1 - 5.1.16

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External links
http://www.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.4.182
http://www.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.9.182
http://www.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.14.127
http://www.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.19.52
http://mirrors.edge.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.1.11
http://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.2

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

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