Vulnerability identifier: #VU52763

Vulnerability risk: High

CVSSv3.1: 7.7 [CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2021-21372

CWE-ID: CWE-94

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
nim
Universal components / Libraries / Programming Languages & Components

Vendor: nim-lang.org

Description

The vulnerability allows a remote attacker to execute arbitrary code on the target system.

The vulnerability exists due to improper input validation in Nimble doCmd when processing entries in the packages.json package. A remote attacker can create a specially crafted entry in the packages.json file, trick the victim into loading the malicious package file and execute arbitrary code on the system.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

nim: 1.2.0 - 1.4.2

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External links
http://consensys.net/diligence/vulnerabilities/nim-insecure-ssl-tls-defaults-remote-code-execution/
http://github.com/nim-lang/nimble/blob/master/changelog.markdown#0130
http://github.com/nim-lang/nimble/commit/7bd63d504a4157b8ed61a51af47fb086ee818c37
http://github.com/nim-lang/security/security/advisories/GHSA-rg9f-w24h-962p

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.