#VU48695 Out-of-bounds read in libslirp - CVE-2020-29129

Vulnerability identifier: #VU48695

Vulnerability risk: Medium

CVSSv4.0: 6.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2020-29129

CWE-ID: CWE-125

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
libslirp
Universal components / Libraries / Libraries used by multiple products

Vendor: Freedesktop.org

Description

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

The vulnerability exists due to buffer over-read in ncsi.c when processing ARP/NCSI packets in 'arp_input' or 'ncsi_input' routines, because the libslirp library tries to read a certain amount of header data even if that exceeds the total packet length. A remote attacker can perform a denial of service attack.

Mitigation
Install update from vendor's website.

Vulnerable software versions

libslirp: 4.0.0 rc0 - 4.3.1

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External links
https://lists.freedesktop.org/archives/slirp/2020-November/000115.html

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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.