OpenSSH up to 7.2 auth-passwd.c auth_password input validation

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

Summaryinfo

A vulnerability was found in OpenSSH up to 7.2. It has been rated as problematic. This impacts the function auth_password of the file auth-passwd.c. The manipulation leads to input validation. This vulnerability is documented as CVE-2016-6515. The attack can be initiated remotely. Additionally, an exploit exists. Upgrading the affected component is advised.

Detailsinfo

A vulnerability was found in OpenSSH up to 7.2 (Connectivity Software) and classified as problematic. This issue affects the function auth_password of the file auth-passwd.c. The manipulation with an unknown input leads to a input validation vulnerability. Using CWE to declare the problem leads to CWE-20. The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly. Impacted is availability. The summary by CVE is:

The auth_password function in auth-passwd.c in sshd in OpenSSH before 7.3 does not limit password lengths for password authentication, which allows remote attackers to cause a denial of service (crypt CPU consumption) via a long string.

The bug was discovered 08/01/2016. The weakness was released 08/07/2016 with Oracle as USN-3061-1 (oss-sec). It is possible to read the advisory at openwall.com. The identification of this vulnerability is CVE-2016-6515 since 08/01/2016. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. Technical details as well as a public exploit are known.

The exploit is available at exploit-db.com. It is declared as proof-of-concept. The vulnerability was handled as a non-public zero-day exploit for at least 6 days. During that time the estimated underground price was around $25k-$100k. The vulnerability scanner Nessus provides a plugin with the ID 93735 (SUSE SLES11 Security Update : openssh (SUSE-SU-2016:2388-1)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family SuSE Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 196559 (Ubuntu Security Notification for Openssh Vulnerabilities (USN-3061-1)).

Upgrading to version 7.3 eliminates this vulnerability. A possible mitigation has been published 2 months after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at Exploit-DB (40888), Tenable (93735) and SecurityFocus (BID 92212†). Entries connected to this vulnerability are available at VDB-21337, VDB-63776, VDB-89622 and VDB-96545. Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

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License

CPE 2.3info

CPE 2.2info

Video

Youtube: Not available anymore

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.4
VulDB Meta Temp Score: 6.1

VulDB Base Score: 5.3
VulDB Temp Score: 4.8
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: Input validation
CWE: CWE-20
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Access: Public
Status: Proof-of-Concept
Download: 🔍

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 93735
Nessus Name: SUSE SLES11 Security Update : openssh (SUSE-SU-2016:2388-1)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 860763
OpenVAS Name: OpenSSH auth_password Denial of Service Vulnerability (Windows)
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Exploit-DB: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

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

Upgrade: OpenSSH 7.3
Patch: github.com

Timelineinfo

08/01/2016 🔍
08/01/2016 +0 days 🔍
08/01/2016 +0 days 🔍
08/07/2016 +6 days 🔍
08/07/2016 +0 days 🔍
08/08/2016 +1 days 🔍
09/26/2016 +49 days 🔍
09/27/2016 +1 days 🔍
10/24/2024 +2948 days 🔍

Sourcesinfo

Advisory: USN-3061-1
Organization: Oracle
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2016-6515 (🔍)
GCVE (CVE): GCVE-0-2016-6515
GCVE (VulDB): GCVE-100-90671

OVAL: 🔍

SecurityFocus: 92212 - OpenSSH CVE-2016-6515 Denial of Service Vulnerability
SecurityTracker: 1036487

scip Labs: https://www.scip.ch/en/?labs.20161013
See also: 🔍

Entryinfo

Created: 08/08/2016 15:29
Updated: 10/24/2024 01:47
Changes: 08/08/2016 15:29 (85), 07/29/2019 10:06 (7), 09/13/2022 12:19 (5), 10/24/2024 01:47 (14)
Complete: 🔍
Cache ID: 216:F58:103

Be aware that VulDB is the high quality source for vulnerability data.

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