Off-by-one error in libx11 (Alpine package)

1) Off-by-one error

EUVDB-ID: #VU14503

Risk: High

CVSSv4.0: 8.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber]

CVE-ID: CVE-2018-14599

CWE-ID: CWE-193 - Off-by-one Error

Exploit availability: No

Description

The vulnerability allows a remote attacker to execute arbitrary code on the target system.

The vulnerability exists due to an off-by-one memory write error in the XGetFontPath(), XListExtensions(), and XListFonts() functions. A remote unauthenticated attacker can cause a remote X server to return a specially crafted response to trigger memory corruption and execute arbitrary code on the target X client.

Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.

Mitigation

Install update from vendor's website.

Vulnerable software versions

libx11 (Alpine package): 1.6.4-r0 - 1.6.5-r2

CPE2.3

• cpe:2.3:a:alpine:libx11_alpine_package:1.6.4-r0:*:*:*:*:alpine_linux:*:3.4
• cpe:2.3:a:alpine:libx11_alpine_package:1.6.5-r0:*:*:*:*:alpine_linux:*:3.5
• cpe:2.3:a:alpine:libx11_alpine_package:1.6.5-r1:*:*:*:*:alpine_linux:*:3.6

External links

https://git.alpinelinux.org/aports/commit/?id=ed32bc3bc0848f7aa57c0f0533d62ba6ef086ceb
https://git.alpinelinux.org/aports/commit/?id=96b4ffd87fea35a16d73bdf288b2dcbe5d15bc82
https://git.alpinelinux.org/aports/commit/?id=bcd0f76d147745372d23b1840ff44b000c95bd81
https://git.alpinelinux.org/aports/commit/?id=d7c441ba3f0fdfc555c09ca51f315ba46459eaa4
https://git.alpinelinux.org/aports/commit/?id=e9064e9114d515f0f789828a1b8c7390c135f541
https://git.alpinelinux.org/aports/commit/?id=f673b89cd43dc3fe12a443558e82318ed03fb6ef

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.