CVE-2021-29495

Name: CVE-2021-29495
Creator: NVD / NIST
Published: 2021-05-07T16:15:08.347+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 7.5/10EPSS 0.49%

Last modified Jun 17, 2026

CVE-2021-29495 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. Nim is a statically typed compiled systems programming language. In Nim standard library before 1.4.2, httpClient SSL/TLS certificate verification was disabled by default. EPSS estimates a 0.49% chance of exploitation in the next 30 days.

Description

Nim is a statically typed compiled systems programming language. In Nim standard library before 1.4.2, httpClient SSL/TLS certificate verification was disabled by default. Users can upgrade to version 1.4.2 to receive a patch or, as a workaround, set "verifyMode = CVerifyPeer" as documented.

Metrics

CVSS 3.1

7.5/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

EPSS Probability

0.49%

38.4th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Nim-Lang	Nim	< 1.4.2

References

https://github.com/nim-lang/security/security/advisories/GHSA-9vqv-2jj9-7mqrThird Party Advisory
https://github.com/nim-lang/security/security/advisories/GHSA-9vqv-2jj9-7mqrThird Party Advisory

Timeline

Published: May 7, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-29495?

How severe is CVE-2021-29495?

CVE-2021-29495 has a CVSS score of 7.5/10 (HIGH severity). The EPSS model estimates a 0.49% probability of exploitation in the next 30 days.

How do I fix CVE-2021-29495?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-29495?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST