OpenSSH 6.8/6.9 sshd access control

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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3.8$0-$5k0.00

Summaryinfo

A vulnerability was found in OpenSSH 6.8/6.9. It has been declared as problematic. This affects an unknown part of the component sshd. Executing a manipulation can lead to access control. This vulnerability appears as CVE-2015-6565. The attack requires local access. In addition, an exploit is available.

Detailsinfo

A vulnerability was found in OpenSSH 6.8/6.9 (Connectivity Software). It has been declared as problematic. This vulnerability affects some unknown processing of the component sshd. The manipulation with an unknown input leads to a access control vulnerability. The CWE definition for the vulnerability is CWE-264. As an impact it is known to affect availability. CVE summarizes:

sshd in OpenSSH 6.8 and 6.9 uses world-writable permissions for TTY devices, which allows local users to cause a denial of service (terminal disruption) or possibly have unspecified other impact by writing to a device, as demonstrated by writing an escape sequence.

The weakness was presented 08/24/2015 as confirmed mailinglist post (oss-sec). The advisory is available at seclists.org. This vulnerability was named CVE-2015-6565 since 08/21/2015. Local access is required to approach this attack. No form of authentication is required for a successful exploitation. Technical details are unknown but a public exploit is available. This vulnerability is assigned to T1068 by the MITRE ATT&CK project.

A public exploit has been developed by Federico Bento and been published 2 years after the advisory. It is possible to download the exploit at exploit-db.com. It is declared as proof-of-concept. As 0-day the estimated underground price was around $5k-$25k. The vulnerability scanner Nessus provides a plugin with the ID 85594 (FreeBSD : OpenSSH -- PAM vulnerabilities (2920c449-4850-11e5-825f-c80aa9043978)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family FreeBSD Local Security Checks. The commercial vulnerability scanner Qualys is able to test this issue with plugin 38658 (OpenSSH TTY Permissions Denial of Service Vulnerability).

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the databases at X-Force (105883), Exploit-DB (41173), Tenable (85594), SecurityFocus (BID 76497†) and Vulnerability Center (SBV-52286†). See VDB-77396, VDB-77397 and VDB-78828 for similar entries. Once again VulDB remains the best source for vulnerability data.

Productinfo

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Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.0
VulDB Meta Temp Score: 3.8

VulDB Base Score: 4.0
VulDB Temp Score: 3.8
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv2info

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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Access control
CWE: CWE-264
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: No

Availability: 🔍
Access: Public
Status: Proof-of-Concept
Author: Federico Bento
Download: 🔍

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 85594
Nessus Name: FreeBSD : OpenSSH -- PAM vulnerabilities (2920c449-4850-11e5-825f-c80aa9043978)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍

OpenVAS ID: 103247
OpenVAS Name: OpenSSH Denial of Service Vulnerability
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Exploit-DB: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

Exploit Delay Time: 🔍

Timelineinfo

08/21/2015 🔍
08/23/2015 +2 days 🔍
08/23/2015 +0 days 🔍
08/23/2015 +0 days 🔍
08/24/2015 +1 days 🔍
08/24/2015 +0 days 🔍
08/25/2015 +1 days 🔍
01/26/2017 +520 days 🔍
01/26/2017 +0 days 🔍
11/18/2024 +2853 days 🔍

Sourcesinfo

Advisory: seclists.org
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2015-6565 (🔍)
GCVE (CVE): GCVE-0-2015-6565
GCVE (VulDB): GCVE-100-77398
X-Force: 105883 - OpenSSH sshd denial of service
SecurityFocus: 76497 - OpenSSH CVE-2015-6565 Local Security Bypass Vulnerability
SecurityTracker: 1033917
Vulnerability Center: 52286 - OpenSSH 6.8 and 6.9 Local DoS and Host Privileges via Writing to a Device, High

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

Entryinfo

Created: 08/24/2015 10:17
Updated: 11/18/2024 09:18
Changes: 08/24/2015 10:17 (54), 03/02/2018 10:13 (25), 06/13/2022 08:53 (3), 06/13/2022 08:54 (1), 11/18/2024 09:18 (16)
Complete: 🔍
Cache ID: 216:396:103

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