#VU52764 Cleartext transmission of sensitive information in nim - CVE-2021-21373

Vulnerability identifier: #VU52764

Vulnerability risk: High

CVSSv4.0: 7.2 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber]

CVE-ID: CVE-2021-21373

CWE-ID: CWE-319

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 perform MitM attack.

The vulnerability exists due to "nimble refresh" tries to fetch a list of Nimble packages over HTTP connection in case HTTPS connection fails. A remote attacker can perform MitM attack and deliver a modified package list containing malicious software packages

Mitigation
Install updates from vendor's website.

Vulnerable software versions

nim: 1.2.0 - 1.4.2

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External links
https://consensys.net/diligence/vulnerabilities/nim-insecure-ssl-tls-defaults-remote-code-execution/
https://github.com/nim-lang/nimble/blob/master/changelog.markdown#0130
https://github.com/nim-lang/security/security/advisories/GHSA-8w52-r35x-rgp8

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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.