OpenSSL up to 1.0.2a DH ssl/s3_clnt.c ssl3_get_key_exchange numeric error

CVSS Meta Temp Score
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CTI Interest Score
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6.5$0-$5k0.00

A vulnerability classified as critical was found in OpenSSL up to 1.0.2a (Network Encryption Software). Affected by this vulnerability is the function ssl3_get_key_exchange of the file ssl/s3_clnt.c of the component DH Handler. The manipulation of the argument p with the input value 0 leads to a numeric error vulnerability. The CWE definition for the vulnerability is CWE-189. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

The ssl3_get_key_exchange function in ssl/s3_clnt.c in OpenSSL 1.0.2 before 1.0.2e allows remote servers to cause a denial of service (segmentation fault) via a zero p value in an anonymous Diffie-Hellman (DH) ServerKeyExchange message.

The weakness was disclosed 12/03/2015 (Website). The advisory is shared at git.openssl.org. This vulnerability is known as CVE-2015-1794 since 02/17/2015. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Technical details are known, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 87213 (FreeBSD : openssl -- multiple vulnerabilities (4c8d1d72-9b38-11e5-aece-d050996490d0)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family FreeBSD Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 43463 (Cisco NX-OS OpenSSL Multiple Vulnerabilities (cisco-sa-20151204-openssl)).

Upgrading to version 1.0.2b eliminates this vulnerability. A possible mitigation has been published 2 days after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at X-Force (108539) and Tenable (87213). The entries 79410, 79411, 79412 and 79413 are pretty similar.

Productinfo

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Name

Version

License

Support

  • end of life (old version)

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB CVSS-B Score: 🔍
VulDB CVSS-BT Score: 🔍
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CVSSv3info

VulDB Meta Base Score: 7.5
VulDB Meta Temp Score: 6.5

VulDB Base Score: 7.5
VulDB Temp Score: 6.5
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv2info

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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
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Exploitinginfo

Class: Numeric error
CWE: CWE-189
ATT&CK: Unknown

Local: No
Remote: Yes

Availability: 🔍
Status: Unproven

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EPSS Percentile: 🔍

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Current Price Estimation: 🔍

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Nessus ID: 87213
Nessus Name: FreeBSD : openssl -- multiple vulnerabilities (4c8d1d72-9b38-11e5-aece-d050996490d0)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 800316
OpenVAS Name: Cisco Adaptive Security Appliance Multiple Vulnerabilities in OpenSSL
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

Interest: 🔍
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Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

Reaction Time: 🔍
0-Day Time: 🔍
Exposure Time: 🔍

Upgrade: OpenSSL 1.0.2b
Patch: ada57746b6b80beae73111fe1291bf8dd89af91c

Timelineinfo

02/17/2015 🔍
12/03/2015 +289 days 🔍
12/05/2015 +2 days 🔍
12/06/2015 +1 days 🔍
12/06/2015 +0 days 🔍
12/07/2015 +1 days 🔍
12/07/2015 +0 days 🔍
12/07/2015 +0 days 🔍
06/28/2022 +2395 days 🔍

Sourcesinfo

Product: openssl.org

Advisory: USN-2830-1
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2015-1794 (🔍)
X-Force: 108539 - OpenSSL ServerKeyExchange denial of service
SecurityTracker: 1034294
Vulnerability Center: 54810 - OpenSSL 1.0.2 - 1.0.2d Remote DoS via a Zero P Value in an DH ServerKeyExchange Message, Medium

See also: 🔍

Entryinfo

Created: 12/07/2015 09:29
Updated: 06/28/2022 14:28
Changes: 12/07/2015 09:29 (60), 05/11/2018 12:58 (20), 06/28/2022 14:28 (6)
Complete: 🔍

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