GNU sharutils 4.2.1 unshar.c symlink

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

A vulnerability, which was classified as problematic, was found in GNU sharutils 4.2.1. This affects an unknown code block of the file unshar.c. The manipulation with an unknown input leads to a symlink vulnerability. CWE is classifying the issue as CWE-61. The product, when opening a file or directory, does not sufficiently account for when the file is a symbolic link that resolves to a target outside of the intended control sphere. This could allow an attacker to cause the product to operate on unauthorized files. This is going to have an impact on integrity. The summary by CVE is:

unshar (unshar.c) in sharutils 4.2.1 allows local users to overwrite arbitrary files via a symlink attack on the unsh.X temporary file.

The bug was discovered 04/04/2005. The weakness was released 05/02/2005 by Joey Hess (Website). It is possible to read the advisory at redhat.com. This vulnerability is uniquely identified as CVE-2005-0990 since 04/06/2005. The exploitability is told to be easy. Attacking locally is a requirement. No form of authentication is needed for exploitation. Technical details of the vulnerability are known, but there is no available exploit.

The vulnerability was handled as a non-public zero-day exploit for at least 27 days. During that time the estimated underground price was around $0-$5k. The vulnerability scanner Nessus provides a plugin with the ID 18952 (FreeBSD : sharutils -- unshar insecure temporary file creation (5f003a08-ba3c-11d9-837d-000e0c2e438a)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family FreeBSD Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 117969 (CentOS Security Update for sharutils (CESA-2005:377)).

Upgrading eliminates this vulnerability. A possible mitigation has been published even before and not after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at X-Force (19957) and Tenable (18952). Entries connected to this vulnerability are available at 22889 and 22890.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

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

Class: Symlink
CWE: CWE-61 / CWE-59
CAPEC: 🔍
ATT&CK: 🔍

Local: Yes
Remote: No

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 18952
Nessus Name: FreeBSD : sharutils -- unshar insecure temporary file creation (5f003a08-ba3c-11d9-837d-000e0c2e438a)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍
Nessus Port: 🔍

OpenVAS ID: 52541
OpenVAS Name: FreeBSD Ports: sharutils
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

Interest: 🔍
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Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Timelineinfo

04/04/2005 🔍
04/04/2005 +0 days 🔍
04/04/2005 +0 days 🔍
04/06/2005 +2 days 🔍
04/11/2005 +5 days 🔍
05/01/2005 +20 days 🔍
05/02/2005 +1 days 🔍
05/02/2005 +0 days 🔍
07/13/2005 +72 days 🔍
03/10/2015 +3527 days 🔍
06/04/2019 +1547 days 🔍

Sourcesinfo

Vendor: gnu.org

Advisory: redhat.com
Researcher: Joey Hess
Status: Not defined

CVE: CVE-2005-0990 (🔍)
OVAL: 🔍

X-Force: 19957
Vulnerability Center: 7551 - Symlink Attack in Sharutils 4.2, 4.2.1 Program \x27unshar.c\x27, Medium
SecurityFocus: 12981 - GNU Sharutils Unshar Local Insecure Temporary File Creation Vulnerability
OSVDB: 15260 - CVE-2005-0990 - GNU - Sharutils - File Execution Issue

See also: 🔍

Entryinfo

Created: 03/10/2015 23:05
Updated: 06/04/2019 18:15
Changes: 03/10/2015 23:05 (75), 06/04/2019 18:15 (5)
Complete: 🔍

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