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Vulnerability record · CVE-2011-4121 · published 26 November 2019

CVE-2011-4121: Ruby-lang ruby inadequate encryption strength vulnerability

Ruby Lang · Ruby

The OpenSSL extension of Ruby (Git trunk) versions after 2011-09-01 up to 2011-11-03 always generated an exponent value of '1' to be used for private RSA key generation. A remote attacker could use this flaw to bypass or corrupt integrity of services, depending on strong private RSA keys generation mechanism.

9.8 CVSS 3.1 Critical EPSS 2.5% · top 15.7% CWE-326 · Inadequate encryption strength
9.8CVSS 3.1 base score, v2 7.5
2.5%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
8References
16 Jun 2026Last modified by NVD

Description

The OpenSSL extension of Ruby (Git trunk) versions after 2011-09-01 up to 2011-11-03 always generated an exponent value of '1' to be used for private RSA key generation. A remote attacker could use this flaw to bypass or corrupt integrity of services, depending on strong private RSA keys generation mechanism.

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
http://www.openwall.com/lists/oss-security/2013/07/01/1 Mailing ListThird Party Advisory
https://access.redhat.com/security/cve/cve-2011-4121 Third Party Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2011-4121 Issue TrackingThird Party Advisory
https://security-tracker.debian.org/tracker/CVE-2011-4121 Third Party Advisory
http://www.openwall.com/lists/oss-security/2013/07/01/1 Mailing ListThird Party Advisory
https://access.redhat.com/security/cve/cve-2011-4121 Third Party Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2011-4121 Issue TrackingThird Party Advisory
https://security-tracker.debian.org/tracker/CVE-2011-4121 Third Party Advisory

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Source: NIST National Vulnerability Database (record CVE-2011-4121), CISA KEV, FIRST EPSS (scores of 2026-09-27). This page is refreshed as NVD updates the record.