CVE Vulnerabilities

CVE-2021-3984

Heap-based Buffer Overflow

Published: Dec 01, 2021 | Modified: Nov 07, 2023
CVSS 3.x
7.8
HIGH
Source:
NVD
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
CVSS 2.x
6.8 MEDIUM
AV:N/AC:M/Au:N/C:P/I:P/A:P
RedHat/V2
RedHat/V3
7.3 MODERATE
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:H/A:H
Ubuntu
MEDIUM

vim is vulnerable to Heap-based Buffer Overflow

Weakness

A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc().

Affected Software

Name Vendor Start Version End Version
Vim Vim * 8.2.3625 (excluding)
Red Hat Enterprise Linux 8 RedHat vim-2:8.0.1763-16.el8_5.4 *
Red Hat Enterprise Linux 8 RedHat vim-2:8.0.1763-16.el8_5.4 *
Vim Ubuntu bionic *
Vim Ubuntu esm-infra/xenial *
Vim Ubuntu focal *
Vim Ubuntu hirsute *
Vim Ubuntu impish *
Vim Ubuntu trusty *
Vim Ubuntu trusty/esm *
Vim Ubuntu upstream *
Vim Ubuntu xenial *

Potential Mitigations

  • Use automatic buffer overflow detection mechanisms that are offered by certain compilers or compiler extensions. Examples include: the Microsoft Visual Studio /GS flag, Fedora/Red Hat FORTIFY_SOURCE GCC flag, StackGuard, and ProPolice, which provide various mechanisms including canary-based detection and range/index checking.
  • D3-SFCV (Stack Frame Canary Validation) from D3FEND [REF-1334] discusses canary-based detection in detail.
  • Run or compile the software using features or extensions that randomly arrange the positions of a program’s executable and libraries in memory. Because this makes the addresses unpredictable, it can prevent an attacker from reliably jumping to exploitable code.
  • Examples include Address Space Layout Randomization (ASLR) [REF-58] [REF-60] and Position-Independent Executables (PIE) [REF-64]. Imported modules may be similarly realigned if their default memory addresses conflict with other modules, in a process known as “rebasing” (for Windows) and “prelinking” (for Linux) [REF-1332] using randomly generated addresses. ASLR for libraries cannot be used in conjunction with prelink since it would require relocating the libraries at run-time, defeating the whole purpose of prelinking.
  • For more information on these techniques see D3-SAOR (Segment Address Offset Randomization) from D3FEND [REF-1335].

References