Improper verification of cryptographic signature in phpseclib - CVE-2021-30130
Published: June 7, 2023 / Updated: May 21, 2026
Vulnerability identifier: #VU77055
CSH Severity: Medium
CVSS v4.0: 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
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vendor: phpseclib
Affected software:
phpseclib
phpseclib
Detailed vulnerability 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.
How to mitigate CVE-2021-30130
Install updates from vendor's website.
Sources
- 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
- https://github.com/phpseclib/phpseclib/security/advisories/GHSA-8p5q-f4jq-7rr3