OpenSSH up to 8.7 Login Session information exposure

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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4.7$0-$5k0.00

Summaryinfo

A vulnerability identified as problematic has been detected in OpenSSH up to 8.7. Impacted is an unknown function of the component Login Session Handler. This manipulation causes information exposure. This vulnerability is tracked as CVE-2016-20012. The attack is possible to be carried out remotely. No exploit exists. It is suggested to install a patch to address this issue.

Detailsinfo

A vulnerability classified as problematic was found in OpenSSH up to 8.7 (Connectivity Software). Affected by this vulnerability is some unknown functionality of the component Login Session Handler. The manipulation with an unknown input leads to a information exposure vulnerability. The CWE definition for the vulnerability is CWE-203. The product behaves differently or sends different responses under different circumstances in a way that is observable to an unauthorized actor, which exposes security-relevant information about the state of the product, such as whether a particular operation was successful or not. As an impact it is known to affect confidentiality. The summary by CVE is:

OpenSSH through 8.7 allows remote attackers, who have a suspicion that a certain combination of username and public key is known to an SSH server, to test whether this suspicion is correct. This occurs because a challenge is sent only when that combination could be valid for a login session. NOTE: the vendor does not recognize user enumeration as a vulnerability for this product

The weakness was disclosed 09/16/2021. The advisory is shared at github.com. This vulnerability is known as CVE-2016-20012 since 09/15/2021. Neither technical details nor an exploit are publicly available. MITRE ATT&CK project uses the attack technique T1592 for this issue.

Applying a patch is able to eliminate this problem. The bugfix is ready for download at github.com.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Type

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.8
VulDB Meta Temp Score: 4.7

VulDB Base Score: 3.7
VulDB Temp Score: 3.6
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 5.3
NVD Vector: 🔍

ADP CISA Base Score: 5.3
ADP CISA 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: Information exposure
CWE: CWE-203 / CWE-200 / CWE-284
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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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Patch
Status: 🔍

0-Day Time: 🔍

Patch: github.com

Timelineinfo

09/15/2021 🔍
09/16/2021 +1 days 🔍
09/16/2021 +0 days 🔍
05/30/2026 +1717 days 🔍

Sourcesinfo

Advisory: github.com
Status: Confirmed

CVE: CVE-2016-20012 (🔍)
GCVE (CVE): GCVE-0-2016-20012
GCVE (VulDB): GCVE-100-182737

Entryinfo

Created: 09/16/2021 03:05
Updated: 05/30/2026 20:42
Changes: 09/16/2021 03:05 (39), 09/19/2021 08:55 (1), 08/06/2024 10:14 (34), 05/30/2026 20:42 (12)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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