Out-of-bounds read in libslirp (Alpine package)

1) Out-of-bounds read

EUVDB-ID: #VU48695

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 - Out-of-bounds read

Exploit availability: No

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 (Alpine package): 4.2.0-r0 - 4.3.1-r0

CPE2.3

• cpe:2.3:o:alpine:libslirp_alpine_package:4.2.0-r0:*:*:*:*:alpine_linux:*:3.11
• cpe:2.3:o:alpine:libslirp_alpine_package:4.3.0-r0:*:*:*:*:alpine_linux:*:3.12
• cpe:2.3:o:alpine:libslirp_alpine_package:4.3.1-r0:*:*:*:*:alpine_linux:*:3.12

External links

https://git.alpinelinux.org/aports/commit/?id=9c57cee80c81eaf5260a4d2c6cb780491138f7f5

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.