CVE-2021-21373

Public Exploit
Nimble falls back to insecure http url when fetching packages

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 by default. In case of error it falls back to a non-TLS URL http://irclogs.nim-lang.org/packages.json. 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

7.5
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.16%
Third-Party Advisory consensys.net 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-8w52-r35x-rgp8 third party advisory

Frequently Asked Questions

What is the severity of CVE-2021-21373?
CVE-2021-21373 has been scored as a high severity vulnerability.
How to fix CVE-2021-21373?
To fix CVE-2021-21373, 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-2021-21373 being actively exploited in the wild?
It is possible that CVE-2021-21373 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-2021-21373?
CVE-2021-21373 affects nim-lang security.
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