What is CVE-2021-30130?

CVE-2021-30130 is a high-severity vulnerability in Phpseclib, classified under Improper Verification of Cryptographic Signature. CVSS score: 7.5/10. Published 2021-04-06.

How severe is CVE-2021-30130?

High severity. CVSS v3 base score is 7.5 out of 10.

Vulnerability in Phpseclib

CVE-2021-30130

phpseclib before 2.0.31 and 3.x before 3.0.7 mishandles RSA PKCS#1 v1.5 signature verification.

Published 2021-04-06 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N.

EPSS exploit prediction

EPSS: 0.011 (63.0th percentile), scored 2026-09-29.

Low probability of exploitation in the next 30 days, but still tracked. 63rd percentile — 63.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.011 · newest: 0.011 · change: 0.000

Affected products

Phpseclib
Debian Linux — versions 10.0

Weakness classification (CWE)

CWE-347 — Improper Verification of Cryptographic Signature

References

github.com/phpseclib/phpseclib/pull/1635 (Patch, Third Party Advisory)
github.com/phpseclib/phpseclib/releases/tag/3.0.7 (Third Party Advisory, Release Notes)
github.com/phpseclib/phpseclib/releases/tag/2.0.31 (Third Party Advisory, Release Notes)
lists.debian.org/debian-lts-announce/2022/11/msg00024.html (mailing-list, Mailing List, Third Party Advisory)
lists.debian.org/debian-lts-announce/2022/11/msg00025.html (mailing-list, Mailing List, Third Party Advisory)

Frequently asked questions

What is CVE-2021-30130?: CVE-2021-30130 is a high-severity vulnerability in Phpseclib, classified under Improper Verification of Cryptographic Signature. CVSS score: 7.5/10. Published 2021-04-06.
How severe is CVE-2021-30130?: High severity. CVSS v3 base score is 7.5 out of 10.