CVE-2021-29495 — Nim stdlib httpClient does not validate peer certificates by default

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.

Published May 7, 2021Updated Aug 3, 2024Sources: cvelistV5, GitHub_M

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the scoring sources call it.

Exploitation

Unreported

no source claims exploitation

EPSS

chance of exploitation in 30 days

Affects

nim lang

security

CVSS base

5.9

MEDIUM

Affected scope

The catalog records vendors and products as separate lists, not pairs, so which product belongs to which vendor is not something this page can say.

Vendors (1)

nim lang

Products (1)

security

Every base score collected

Sources score independently and disagree; each row says who scored it and under which version.

Score	Version	Severity	Expl.	Impact	Source
5.9	CVSS 3.1	MEDIUM	—	—	cvelistV5

Weakness & attack patterns

CWE-295

Detection

Read off the CVSS vector and the weakness class. Starting points, not rules we have tested.

Search application, proxy, and WAF logs for requests touching /TLS.

References

1 on the record

github.com/nim-lang/security/security/advisories/GHSA-9vqv-2jj9-7mqr
x_refsource_CONFIRM

Elsewhere on this site

nim langevery CVE for this vendor
CWE-295other pages naming this weakness

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
No exploit packet captures, log samples, or incident case IDs supplied.