OpenSSL 1.0.1e-25.el7 on Red Hat Lock Mechanism ssleay_rand_bytes race condition

CVSS Meta Temp Score
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CTI Interest Score
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A vulnerability classified as problematic has been found in OpenSSL 1.0.1e-25.el7 on Red Hat (Network Encryption Software). This affects the function ssleay_rand_bytes of the component Lock Mechanism. The manipulation with an unknown input leads to a race condition vulnerability. CWE is classifying the issue as CWE-362. This is going to have an impact on availability.

The issue has been introduced in 02/11/2013. The weakness was released 06/15/2015 by Johannes Bauer as RHSA-2015-1115 as confirmed advisory (Website). It is possible to read the advisory at This vulnerability is uniquely identified as CVE-2015-3216 since 04/10/2015. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. Technical details of the vulnerability are known, but there is no available exploit. The advisory points out:

A flaw was found in the way the OpenSSL packages shipped with Red Hat Enterprise Linux 6 and 7 performed locking in the ssleay_rand_bytes() function. This issue could possibly cause a multi-threaded application using OpenSSL to perform an out-of-bounds read and crash.

The vulnerability was handled as a non-public zero-day exploit for at least 854 days. During that time the estimated underground price was around $5k-$25k. The vulnerability scanner Nessus provides a plugin with the ID 84203 (OracleVM 3.3 : openssl (OVMSA-2015-0070)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family OracleVM Local Security Checks. The commercial vulnerability scanner Qualys is able to test this issue with plugin 350152 (Amazon Linux Security Advisory for openssl: ALAS-2015-550).

Applying a patch is able to eliminate this problem.

The vulnerability is also documented in the databases at SecurityFocus (BID 75219), X-Force (103915), SecurityTracker (ID 1032587), Vulnerability Center (SBV-51031) and Tenable (84203). Entries connected to this vulnerability are available at 75496, 78627, 78668 and 80581.


  • Red Hat Enterprise Linux 6/7




CPE 2.3infoedit

CPE 2.2infoedit


VulDB Meta Base Score: 5.3
VulDB Meta Temp Score: 4.6

VulDB Base Score: 5.3
VulDB Temp Score: 4.6
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Class: Race condition
CWE: CWE-362
ATT&CK: Unknown

Local: No
Remote: Yes

Availability: 🔍
Status: Unproven

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Nessus ID: 84203
Nessus Name: OracleVM 3.3 : openssl (OVMSA-2015-0070)
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OpenVAS ID: 10462
OpenVAS Name: RedHat Update for openssl RHSA-2015:1115-01
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Threat Intelligenceinfoedit

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Recommended: Patch
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02/11/2013 🔍
04/10/2015 +788 days 🔍
05/28/2015 +48 days 🔍
05/28/2015 +0 days 🔍
06/15/2015 +18 days 🔍
06/16/2015 +1 days 🔍
06/17/2015 +1 days 🔍
07/07/2015 +20 days 🔍
07/08/2015 +1 days 🔍
01/16/2017 +558 days 🔍
09/16/2017 +243 days 🔍



Advisory: RHSA-2015-1115
Researcher: Johannes Bauer
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2015-3216 (🔍)

SecurityFocus: 75219 - OpenSSL 'ssleay_rand_bytes()' Function Denial of Service Vulnerability
X-Force: 103915 - OpenSSL shipped with Red Hat Enterprise Linux ssleay_rand_bytes() denial of service
SecurityTracker: 1032587 - Red Hat OpenSSL Locking Error in ssleay_rand_bytes() Lets Remote Users Deny Service
Vulnerability Center: 51031 - OpenSSL Remote DoS due to Many TLS Sessions in the Ssleay_Rand_Bytes Function (), Medium

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Created: 06/17/2015 09:11 AM
Updated: 09/16/2017 10:25 AM
Changes: (13) vulnerability_cvss2_nvd_av vulnerability_cvss2_nvd_ac vulnerability_cvss2_nvd_au vulnerability_cvss2_nvd_ci vulnerability_cvss2_nvd_ii vulnerability_cvss2_nvd_ai advisory_confirm_url source_securityfocus_date source_securityfocus_class source_openvas_id source_openvas_filename source_openvas_title source_openvas_family
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