Nextcloud Desktop Client 2.6.4 on Linux path traversal

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.5$0-$5k0.00

A vulnerability was found in Nextcloud Desktop Client 2.6.4 on Linux (Cloud Software) and classified as critical. This issue affects some unknown functionality. The manipulation with an unknown input leads to a path traversal vulnerability. Using CWE to declare the problem leads to CWE-22. The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

Missing sanitization of a server response in Nextcloud Desktop Client 2.6.4 for Linux allowed a malicious Nextcloud Server to store files outside of the dedicated sync directory.

The weakness was shared 08/21/2020 (Website). The advisory is shared at hackerone.com. The identification of this vulnerability is CVE-2020-8227 since 01/28/2020. The exploitation is known to be difficult. The attack may be initiated remotely. A simple authentication is required for exploitation. It demands that the victim is doing some kind of user interaction. Neither technical details nor an exploit are publicly available. MITRE ATT&CK project uses the attack technique T1006 for this issue.

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

The entry 160168 is related to this item.

Productinfo

Type

Vendor

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

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

VulDB Meta Base Score: 5.5
VulDB Meta Temp Score: 5.5

VulDB Base Score: 4.3
VulDB Temp Score: 4.3
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 6.8
NVD Vector: 🔍

CVSSv2info

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

NVD Base Score: 🔍

Exploitinginfo

Class: Path traversal
CWE: CWE-22
ATT&CK: T1006

Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

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EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Threat Intelligenceinfo

Interest: 🔍
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Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔍

Timelineinfo

01/28/2020 🔍
08/21/2020 +206 days 🔍
08/22/2020 +1 days 🔍
08/22/2020 +0 days 🔍

Sourcesinfo

Advisory: hackerone.com
Status: Not defined

CVE: CVE-2020-8227 (🔍)
See also: 🔍

Entryinfo

Created: 08/22/2020 09:20
Updated: 08/22/2020 09:25
Changes: 08/22/2020 09:20 (38), 08/22/2020 09:25 (18)
Complete: 🔍

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