CVE-2021-3984

HIGH

vim < 8.2.3625 - Heap-based Buffer Overflow

Title source: llm
STIX 2.1

Exploitation Summary

EIP tracks 1 public exploit for CVE-2021-3984. PoCs published by cemonatk.

AI-analyzed exploit summary This repository contains a detailed technical analysis of CVE-2021-3984, a heap-based buffer overflow in Vim. It includes the original report, sanitizer output, and references to patches and advisories, but does not include functional exploit code.

Description

vim is vulnerable to Heap-based Buffer Overflow

Exploits (1)

github WRITEUP 3 stars
by cemonatk · poc
https://github.com/cemonatk/onefuzzyway/tree/main/CVEs/vim/CVE-2021-3984.md

This repository contains a detailed technical analysis of CVE-2021-3984, a heap-based buffer overflow in Vim. It includes the original report, sanitizer output, and references to patches and advisories, but does not include functional exploit code.

Classification
Writeup 95%
Attack Type
Dos
Complexity
Moderate
Reliability
Reliable
Target: Vim (master branch, commit 3cad470)
No auth needed
Prerequisites: Vim compiled with AddressSanitizer · POC file (not included in the repo)
devstral-2 · analyzed Apr 29, 2026 Full analysis →

Scores

CVSS v3 7.8
EPSS 0.0146
EPSS Percentile 70.1%
Attack Vector LOCAL
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Details

CWE
CWE-122 CWE-787
Status published
Products (4)
debian/debian_linux 9.0
debian/debian_linux 10.0
fedoraproject/fedora 34
vim/vim < 8.2.3625
Published Dec 01, 2021
Tracked Since Feb 18, 2026