GNU Patch up to 2.7.6 String pch.c do_ed_script Shell Metacharacter os command injection

Summaryinfo

A vulnerability has been found in GNU Patch up to 2.7.6 and classified as critical. Affected is the function do_ed_script of the file pch.c of the component String Handler. This manipulation as part of Shell Metacharacter causes os command injection. This vulnerability is tracked as CVE-2018-20969. The attack is restricted to local execution. No exploit exists.

Detailsinfo

A vulnerability was found in GNU Patch up to 2.7.6. It has been declared as critical. Affected by this vulnerability is the function do_ed_script of the file pch.c of the component String Handler. The manipulation as part of a Shell Metacharacter leads to a os command injection vulnerability. The CWE definition for the vulnerability is CWE-78. The product constructs all or part of an OS command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended OS command when it is sent to a downstream component. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

do_ed_script in pch.c in GNU patch through 2.7.6 does not block strings beginning with a ! character. NOTE: this is the same commit as for CVE-2019-13638, but the ! syntax is specific to ed, and is unrelated to a shell metacharacter.

The weakness was disclosed 08/16/2019 as not defined mailinglist post (Bugtraq). It is possible to read the advisory at seclists.org. This vulnerability is known as CVE-2018-20969 since 08/15/2019. The attack can be launched remotely. The exploitation doesn't need any form of authentication. It demands that the victim is doing some kind of user interaction. Technical details of the vulnerability are known, but there is no available exploit. The attack technique deployed by this issue is T1202 according to MITRE ATT&CK.

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

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Productinfo

Vendor

• GNU

Name

• Patch

Version

• 2.7.0
• 2.7.1
• 2.7.2
• 2.7.3
• 2.7.4
• 2.7.5
• 2.7.6

License

• open-source

Website

• Vendor: https://www.gnu.org/

CPE 2.3info

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CPE 2.2info

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