CVE-2021-21374

mediumpriority · track · 32EPSS 0.010 · 64 %ileEURUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

1.04% (64th) EPSS

CVSS 6.8 · medium

Is it mine?

7 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · fstec_bdu · nvd

EPSS · scored 2026-10-27

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.

cvss

Technical severity, 0–10. One row per scoring source.

8.1

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.8–8.1

v2.06.8mediumAV:N/AC:M/Au:N/C:P/I:P/A:Pprimary · NVD / NIST USexploitability 8.6 · impact 6.4

v3.18.1highCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:Hprimary · NVD / NIST USexploitability 2.2 · impact 5.9

v3.18.1highAV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:Hsecondary · FSTEC (BDU) RU

v3.18.1highCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:H/A:Lsecondary · ENISA EU

v3.18.1highCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:H/A:Lsecondary · security-advisories@github.comexploitability 2.2 · impact 5.3

v3.17.4highCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-295USprimaryCWE-295USCWE-348USCWE-348USCWE-349USCWE-349USCWE-599USCWE-599US

affected products (7)

Products and version ranges known to be affected.

nim-lang security≤ < 1.2.10enisa_euvdEU
nim-lang security1.4.0, → 1.4.4enisa_euvdEU
Nim Lang Team Nim≤ 1.2.10fstec_bduRU
Nim Lang Team Nim1.4.0 → 1.4.4fstec_bduRU
Nim Lang Team Nimble≤ 0.12.0fstec_bduRU
nim-lang nim< 1.2.10nvdUScpe:2.3:a:nim-lang:nim:*:*:*:*:*:*:*:*
nim-lang nim1.4.0 → 1.4.4nvdUScpe:2.3:a:nim-lang:nim:*:*:*:*:*:*:*:*

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu nvd NVD CVE.org MITRE

published 2021-03-26modified 2026-06-17

related (1,894)

Related entries.

ID	severity	EPSS	exploitable	published
CVE-2026-85102US	—OT critical	54.1% (99th)	KEV	2026-09-09
Improper certificate trust validation during VPN negotiation in Check Point Quantum Security Gateway may allow an unauthenticated remote attacker to execute arbitrary code on the G…
CVE-2023-41991US	medium5.5OT critical	13.4% (96th)	KEV	2023-09-21
A certificate validation issue was addressed. This issue is fixed in macOS Ventura 13.6, iOS 16.7 and iPadOS 16.7. A malicious app may be able to bypass signature validation. Apple…
CVE-2023-20963US	high7.8OT critical	1.47% (74th)	KEV	2023-03-24
In WorkSource, there is a possible parcel mismatch. This could lead to local escalation of privilege with no additional execution privileges needed. User interaction is not needed…
CVE-2022-26923US	high9.0OT critical	83.5% (100th)	KEV	2022-05-10
Active Directory Domain Services Elevation of Privilege Vulnerability
CVE-2022-20703US	high8.0OT critical	9.20% (95th)	KEV	2022-02-10
Multiple vulnerabilities in Cisco Small Business RV160, RV260, RV340, and RV345 Series Routers could allow an attacker to do any of the following: Execute arbitrary code Elevate pr…

+1889 more

references (15)

External citations — patches, advisories, analysis.

scry

Attackers weaponise vulnerabilities like this against internet-exposed services. See what is exposed on your perimeter with a free passive scan.

Free scan