CVE-2021-21374

Public Exploit
Nimble fails to validate certificates due to insecure httpClient defaults

Description

Nimble is a package manager for the Nim programming language. In Nim release versions before versions 1.2.10 and 1.4.4, "nimble refresh" fetches a list of Nimble packages over HTTPS without full verification of the SSL/TLS certificate due to the default setting of httpClient. An attacker able to perform MitM can deliver a modified package list containing malicious software packages. If the packages are installed and used the attack escalates to untrusted code execution.

Categories

8.1
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.27%
Third-Party Advisory consensys.net Third-Party Advisory github.com Third-Party Advisory github.com Third-Party Advisory github.com
Affected: nim-lang security
Published at:
Updated at:

References

Link Tags
https://consensys.net/diligence/vulnerabilities/nim-insecure-ssl-tls-defaults-remote-code-execution/ third party advisory exploit
https://github.com/nim-lang/nimble/blob/master/changelog.markdown#0130 third party advisory release notes
https://github.com/nim-lang/security/security/advisories/GHSA-c2wm-v66h-xhxx third party advisory
https://github.com/nim-lang/Nim/pull/16940 third party advisory patch

Frequently Asked Questions

What is the severity of CVE-2021-21374?
CVE-2021-21374 has been scored as a high severity vulnerability.
How to fix CVE-2021-21374?
To fix CVE-2021-21374, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-21374 being actively exploited in the wild?
It is possible that CVE-2021-21374 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-21374?
CVE-2021-21374 affects nim-lang security.
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