CVE-2011-4121

Name: CVE-2011-4121
Creator: NVD / NIST
Published: 2019-11-26T05:15:13.96+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

CRITICALCVSS 9.8/10EPSS 2.53%

Last modified Jun 16, 2026

CVE-2011-4121 is a critical-severity vulnerability rated 9.8/10 on the CVSS scale. 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.. EPSS estimates a 2.53% chance of exploitation in the next 30 days.

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.

Metrics

CVSS 3.1

9.8/10

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

EPSS Probability

2.53%

82.9th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-326

Affected Software

Vendor	Product	Versions
Ruby-Lang	Ruby	>= 1.8.7.334, < 1.9.3

References

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

Timeline

Published: Nov 26, 2019
Last Modified: Jun 16, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2011-4121?

How severe is CVE-2011-4121?

CVE-2011-4121 has a CVSS score of 9.8/10 (CRITICAL severity). The EPSS model estimates a 2.53% probability of exploitation in the next 30 days.

How do I fix CVE-2011-4121?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2011-4121?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST