Integer overflow in libssh2 (Alpine package)

1) Integer overflow

EUVDB-ID: #VU22574

Risk: High

CVSSv4.0: 5.3 [CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:H/VI:N/VA:H/SC:N/SI:N/SA:N/E:P/U:Amber]

CVE-ID: CVE-2019-17498

CWE-ID: CWE-190 - Integer overflow

Exploit availability: No

Description

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

The vulnerability exists due to integer overflow in the "SSH_MSG_DISCONNECT" logic in "packet.c" in a bounds check. A remote attacker can specify an arbitrary (out-of-bounds) offset for a subsequent memory read, trigger out-of-bounds read, disclose sensitive information or cause a denial of service condition on the target system when a user connects to the malicious SSH server.

Mitigation

Install update from vendor's website.

Vulnerable software versions

IBM Tivoli Storage Manager: 7.1.4.1

libssh2 (Alpine package): 2.11-6

libssh2 (Alpine package): 3.5.22-6 - 3.5.22-7

libssh2 (Alpine package): 2.0.4.1

libssh2 (Alpine package): 20080708-2 - 20090404-1

libssh2 (Alpine package): 1.20130917-1 - 1.20131003-1

libssh2 (Alpine package): 2.9

libssh2 (Alpine package): 0.5.8-0ubuntu1

libssh2 (Alpine package): 1.67ubuntu1

libssh2 (Alpine package): 2.0.43 - 5.0.4

libssh2 (Alpine package): 1.5.28ubuntu1

libssh2 (Alpine package): 0.20-5

libssh2 (Alpine package): 2.2.1-4 - 2.2.1-46-g10887d272-2

libssh2 (Alpine package): 5 - 9

libssh2 (Alpine package): 8.20-3ubuntu2 - 8.21-1ubuntu2

libssh2 (Alpine package): 5.5.1.1

libssh2 (Alpine package): 38.0.1

libssh2 (Alpine package): 6.2.0a

libssh2 (Alpine package): 0.4.5

libssh2 (Alpine package): 7.5.2

libssh2 (Alpine package): 10.0

libssh2 (Alpine package): 9.0.2.881

libssh2 (Alpine package): 7.0.3

libssh2 (Alpine package): 2007

libssh2 (Alpine package):

CPE2.3

• cpe:2.3:a:ibm_corporation:ibm_tivoli_storage_manager:7.1.4.1:*:*:*:*:*:*:*
• cpe:2.3:a:alpine:libssh2_alpine_package:2.11-6:*:*:*:*:alpine_linux:*:*
• cpe:2.3:a:alpine:libssh2_alpine_package:3.5.22-6:*:*:*:*:alpine_linux:*:*
• cpe:2.3:a:alpine:libssh2_alpine_package:3.5.22-7:*:*:*:*:alpine_linux:*:*
• cpe:2.3:a:alpine:libssh2_alpine_package:2.0.4.1:*:*:*:*:alpine_linux:*:*
• cpe:2.3:a:alpine:libssh2_alpine_package:20080708-2:*:*:*:*:alpine_linux:*:*
• cpe:2.3:a:alpine:libssh2_alpine_package:20090404-1:*:*:*:*:alpine_linux:*:*
• cpe:2.3:a:alpine:libssh2_alpine_package:1.20130917-1:*:*:*:*:alpine_linux:*:*
• cpe:2.3:a:alpine:libssh2_alpine_package:1.20131003-1:*:*:*:*:alpine_linux:*:*
• cpe:2.3:a:alpine:libssh2_alpine_package:2.9:*:*:*:*:alpine_linux:*:*
• cpe:2.3:a:alpine:libssh2_alpine_package:0.5.8-0ubuntu1:*:*:*:*:alpine_linux:*:*
• cpe:2.3:a:alpine:libssh2_alpine_package:1.67ubuntu1:*:*:*:*:alpine_linux:*:*
• cpe:2.3:a:alpine:libssh2_alpine_package:2.0.43:*:*:*:*:alpine_linux:*:*
• cpe:2.3:a:alpine:libssh2_alpine_package:1.5.28ubuntu1:*:*:*:*:alpine_linux:*:*
• cpe:2.3:a:alpine:libssh2_alpine_package:0.20-5:*:*:*:*:alpine_linux:*:*
• cpe:2.3:a:alpine:libssh2_alpine_package:2.2.1-4:*:*:*:*:alpine_linux:*:*
• cpe:2.3:a:alpine:libssh2_alpine_package:5:*:*:*:*:alpine_linux:*:*
• cpe:2.3:a:alpine:libssh2_alpine_package:8.20-3ubuntu2:*:*:*:*:alpine_linux:*:*
• cpe:2.3:a:alpine:libssh2_alpine_package:5.5.1.1:*:*:*:*:alpine_linux:*:*
• cpe:2.3:a:alpine:libssh2_alpine_package:38.0.1:*:*:*:*:alpine_linux:*:*
• cpe:2.3:a:alpine:libssh2_alpine_package:6.2.0a:*:*:*:*:alpine_linux:*:*
• cpe:2.3:a:alpine:libssh2_alpine_package:0.4.5:*:*:*:*:alpine_linux:*:*
• cpe:2.3:a:alpine:libssh2_alpine_package:7.5.2:*:*:*:*:alpine_linux:*:*
• cpe:2.3:a:alpine:libssh2_alpine_package:10.0:*:*:*:*:alpine_linux:*:*
• cpe:2.3:a:alpine:libssh2_alpine_package:9.0.2.881:*:*:*:*:alpine_linux:*:*
• cpe:2.3:a:alpine:libssh2_alpine_package:7.0.3:*:*:*:*:alpine_linux:*:*
• cpe:2.3:a:alpine:libssh2_alpine_package:2007:*:*:*:*:alpine_linux:*:*
• cpe:2.3:a:alpine:libssh2_alpine_package::*:*:*:*:alpine_linux:*:*

External links

https://git.alpinelinux.org/aports/commit/?id=d33ef701a0f9572919bab33d45f26a7e53ddb156
https://git.alpinelinux.org/aports/commit/?id=db43cc6825c1432f1f003c621cee428ba844860f
https://git.alpinelinux.org/aports/commit/?id=6c763143a08a56997ee6f88f9329cfc17d6b56b5
https://git.alpinelinux.org/aports/commit/?id=7e5d7dd70d3c19875845f534826625d7071f222d
https://git.alpinelinux.org/aports/commit/?id=abdf2ab6d79a67fd9049354e301836e75be57fce

Q & A

Can this vulnerability be exploited remotely?

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

How the attacker can exploit this vulnerability?

The attacker would have to send a specially crafted request to the affected application in order to exploit this vulnerability.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability. However, proof of concept for this vulnerability is available.