OpenVPN mss.c mss_fixup_ipv6 resource management

CVSS Meta Temp Score
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CTI Interest Score
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6.1$0-$5k0.00

Summaryinfo

A vulnerability labeled as problematic has been found in OpenVPN. The impacted element is the function mss_fixup_ipv6 of the file mss.c. The manipulation results in resource management. This vulnerability is cataloged as CVE-2017-7508. The attack may be launched remotely. There is no exploit available. The affected component should be upgraded.

Detailsinfo

A vulnerability was found in OpenVPN (Network Encryption Software) (the affected version unknown). It has been classified as problematic. Affected is the function mss_fixup_ipv6 of the file mss.c. The manipulation with an unknown input leads to a resource management vulnerability. CWE is classifying the issue as CWE-399. This is going to have an impact on availability. CVE summarizes:

OpenVPN versions before 2.4.3 and before 2.3.17 are vulnerable to remote denial-of-service when receiving malformed IPv6 packet.

The bug was discovered 06/22/2017. The weakness was shared 06/21/2017 by Guido Vranken with https://guidovranken.wordpress.com as The OpenVPN post-audit bug bonanza as not defined blog post (Website). The advisory is available at guidovranken.wordpress.com. This vulnerability is traded as CVE-2017-7508 since 04/05/2017. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. Technical details are known, but there is no available exploit. The reason for this vulnerability is this part of code: 

if (buf_advance( &newbuf, 40 ) )
{
    struct openvpn_tcphdr *tc = (struct openvpn_tcphdr *) BPTR(&newbuf);
    if (tc->flags & OPENVPN_TCPH_SYN_MASK)
    {
        mss_fixup_dowork(&newbuf, (uint16_t) maxmss-20);
    }
}

The vulnerability scanner Nessus provides a plugin with the ID 101064 (Amazon Linux AMI : openvpn (ALAS-2017-852)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Amazon Linux Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 196832 (Ubuntu Security Notification for Openvpn Vulnerabilities (USN-3339-1)).

Upgrading eliminates this vulnerability. The upgrade is hosted for download at openvpn.net. A possible mitigation has been published 6 days after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at Tenable (101064) and SecurityFocus (BID 99230†). The entries VDB-102707, VDB-102708, VDB-102709 and VDB-102710 are related to this item. If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Type

Name

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.4
VulDB Meta Temp Score: 6.3

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 7.5
NVD Vector: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Resource management
CWE: CWE-399 / CWE-404
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 101064
Nessus Name: Amazon Linux AMI : openvpn (ALAS-2017-852)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 703900
OpenVAS Name: Debian Security Advisory DSA 3900-1 (openvpn - security update)
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

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

Upgrade: openvpn.net

Timelineinfo

04/05/2017 🔍
06/21/2017 +77 days 🔍
06/21/2017 +0 days 🔍
06/22/2017 +1 days 🔍
06/22/2017 +0 days 🔍
06/27/2017 +5 days 🔍
06/27/2017 +0 days 🔍
06/28/2017 +1 days 🔍
12/29/2020 +1280 days 🔍

Sourcesinfo

Advisory: The OpenVPN post-audit bug bonanza
Researcher: Guido Vranken
Organization: https://guidovranken.wordpress.com
Status: Not defined
Confirmation: 🔍

CVE: CVE-2017-7508 (🔍)
GCVE (CVE): GCVE-0-2017-7508
GCVE (VulDB): GCVE-100-102714

OVAL: 🔍

SecurityFocus: 99230 - OpenVPN Multiple Security Vulnerabilities
SecurityTracker: 1038768

See also: 🔍

Entryinfo

Created: 06/21/2017 17:48
Updated: 12/29/2020 11:35
Changes: 06/21/2017 17:48 (81), 10/19/2019 14:31 (6), 12/29/2020 11:35 (3)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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