Is CVE-2021-4173 in the CISA KEV catalog?

No. CVE-2021-4173 is not currently on the CISA Known Exploited Vulnerabilities list.

What is the CVSS severity of CVE-2021-4173?

CVE-2021-4173 has a CVSS v3 base score of 7.8 (HIGH).

What is the EPSS score for CVE-2021-4173?

CVE-2021-4173 has an EPSS score of 1.62% (73th percentile), estimating the probability of exploitation in the next 30 days.

How do I fix CVE-2021-4173?

Upgrade vim on debian 11 to 2:8.2.2434-3+deb11u2 or later. Fixes are available for 2 affected products.

CVE & CISA-KEV Catalog

CVE-2021-4173

HIGHEPSS 73th pctl

7.8

CVSS v3

NVD

Description

vim is vulnerable to Use After Free

CWE-416Use After Free

How to fix

Remediation Available

vimDebian

Fixed in:2:8.2.2434-3+deb11u2CVE-2021-4173

Fixed in:2:8.2.3995-1CVE-2021-4173

VimWindows application

Affected:8.2.3902Fixed in:8.2.3902Bram Moolenaar et al.

Remediation is compiled from vendor and distribution security advisories. Always confirm against the linked source for your exact version and platform.

CVSS v3 Vector

Exploitability

Attack VectorLocal

Attack ComplexityLow

Privileges RequiredNone

User InteractionRequired

ScopeUnchanged

Impact

ConfidentialityHigh

IntegrityHigh

AvailabilityHigh

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

Exploit Intelligence

1.62%probability of exploitation in 30 days

73rdpercentile

Elevated risk: more likely to be exploited than 73% of all known CVEs.

References

Patch1

github.com

Exploit1

huntr.dev

Third-Party Advisory8

Other references3

Related Vulnerabilities

Other CWE-416 (Use After Free) vulnerabilities, ordered by exploit likelihood. View all

CVE	Severity	CVSS	EPSS	Exploited	Fix
CVE-2019-0708	Critical	9.8	100%	KEV + Ransom	-
CVE-2021-31166	Critical	9.8	100%	KEV	Fix
CVE-2015-5119	Critical	9.8	99%	KEV	-
CVE-2010-3962	High	8.1	97%	KEV	-
CVE-2015-0313	Critical	9.8	96%	KEV	Fix
CVE-2017-9798	High	7.5	95%	-	Fix

Embed a live status badge for CVE-2021-4173

Markdown

[![CVE-2021-4173](https://tridentstack.com/cve/badge/CVE-2021-4173.svg)](https://tridentstack.com/cve/CVE-2021-4173)

HTML

<a href="https://tridentstack.com/cve/CVE-2021-4173"><img src="https://tridentstack.com/cve/badge/CVE-2021-4173.svg" alt="CVE-2021-4173"></a>

Find and fix vulnerabilities across your fleet

TridentStack Control continuously scans your Windows, macOS, and Linux fleet for known vulnerabilities, prioritizes them by severity and active exploitation, and patches them automatically.

Start free

This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2025-11-03.