MitM attack in phpseclib

1) Improper verification of cryptographic signature

EUVDB-ID: #VU77055

Risk: Medium

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

CVE-ID: CVE-2021-30130

CWE-ID: CWE-347 - Improper Verification of Cryptographic Signature

Exploit availability: No

Description

The vulnerability allows a remote attacker to perform MitM attack.

The vulnerability exists due to improper verification of RSA PKCS#1 v1.5 signature. A remote attacker can perform MitM attack.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

phpseclib: 2.0.0 - 3.0.6

CPE2.3

• cpe:2.3:a:phpseclib:phpseclib:2.0.0:*:*:*:*:*:*:*
• cpe:2.3:a:phpseclib:phpseclib:2.0.1:*:*:*:*:*:*:*
• cpe:2.3:a:phpseclib:phpseclib:2.0.2:*:*:*:*:*:*:*

External links

https://github.com/phpseclib/phpseclib/releases/tag/2.0.31
https://github.com/phpseclib/phpseclib/pull/1635
https://github.com/phpseclib/phpseclib/releases/tag/3.0.7
https://lists.debian.org/debian-lts-announce/2022/11/msg00024.html
https://lists.debian.org/debian-lts-announce/2022/11/msg00025.html

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.