Input validation error in strongswan (Alpine package)

1) Input validation error

EUVDB-ID: #VU32362

Risk: Medium

CVSSv4.0: 2.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2015-8023

CWE-ID: CWE-20 - Improper input validation

Exploit availability: No

Description

The vulnerability allows a remote non-authenticated attacker to manipulate data.

The server implementation of the EAP-MSCHAPv2 protocol in the eap-mschapv2 plugin in strongSwan 4.2.12 through 5.x before 5.3.4 does not properly validate local state, which allows remote attackers to bypass authentication via an empty Success message in response to an initial Challenge message.

Mitigation

Install update from vendor's website.

Vulnerable software versions

strongswan (Alpine package): 5.1.3-r0

CPE2.3

• cpe:2.3:a:alpine:strongswan_alpine_package:5.1.3-r0:*:*:*:*:alpine_linux:*:2.6

External links

https://git.alpinelinux.org/aports/commit/?id=6018b042c328b58a643e2db5997588a1aed58f36
https://git.alpinelinux.org/aports/commit/?id=e5f15c5c5e04dd9392353656258dd3d4c8cb2fbb
https://git.alpinelinux.org/aports/commit/?id=13c552a7cd38c9b1ec455073656e65abb433a94d
https://git.alpinelinux.org/aports/commit/?id=3adb6561f830cc6f7eade5e2c465e3f51bb0324e

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.