---
id: CVE-2021-39537
title: An issue was discovered in ncurses through v6.2-1
summary: >-
  An issue was discovered in ncurses through v6.2-1. _nc_captoinfo in
  captoinfo.c has a heap-based buffer overflow.
severity: high
cvss: 8.8
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H'
cwe:
  - CWE-787
vendor: invisible-island
product: ncurses
affected:
  - ncurses <= 6.2.1
  - mac_os_x = 10.12.6
  - macos = 11.7
  - macos = 13.0
published: '2021-09-20'
updated: '2026-07-27'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2021-39537'
references:
  - url: >-
      http://cvsweb.netbsd.org/bsdweb.cgi/pkgsrc/devel/ncurses/patches/patch-ncurses_tinfo_captoinfo.c?rev=1.1&content-type=text/x-cvsweb-markup
    label: cve@mitre.org
  - url: 'http://seclists.org/fulldisclosure/2022/Oct/28'
    label: cve@mitre.org
  - url: 'http://seclists.org/fulldisclosure/2022/Oct/41'
    label: cve@mitre.org
  - url: 'http://seclists.org/fulldisclosure/2022/Oct/43'
    label: cve@mitre.org
  - url: 'http://seclists.org/fulldisclosure/2022/Oct/45'
    label: cve@mitre.org
  - url: 'https://lists.debian.org/debian-lts-announce/2023/12/msg00004.html'
    label: cve@mitre.org
  - url: 'https://lists.gnu.org/archive/html/bug-ncurses/2020-08/msg00006.html'
    label: cve@mitre.org
  - url: 'https://lists.gnu.org/archive/html/bug-ncurses/2021-10/msg00023.html'
    label: cve@mitre.org
  - url: 'https://security.netapp.com/advisory/ntap-20230427-0012/'
    label: cve@mitre.org
  - url: 'https://support.apple.com/kb/HT213443'
    label: cve@mitre.org
  - url: 'https://support.apple.com/kb/HT213444'
    label: cve@mitre.org
  - url: 'https://support.apple.com/kb/HT213488'
    label: cve@mitre.org
  - url: >-
      http://cvsweb.netbsd.org/bsdweb.cgi/pkgsrc/devel/ncurses/patches/patch-ncurses_tinfo_captoinfo.c?rev=1.1&content-type=text/x-cvsweb-markup
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'http://seclists.org/fulldisclosure/2022/Oct/28'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'http://seclists.org/fulldisclosure/2022/Oct/41'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'http://seclists.org/fulldisclosure/2022/Oct/43'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'http://seclists.org/fulldisclosure/2022/Oct/45'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://lists.debian.org/debian-lts-announce/2023/12/msg00004.html'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://lists.gnu.org/archive/html/bug-ncurses/2020-08/msg00006.html'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://lists.gnu.org/archive/html/bug-ncurses/2021-10/msg00023.html'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://security.netapp.com/advisory/ntap-20230427-0012/'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://support.apple.com/kb/HT213443'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://support.apple.com/kb/HT213444'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://support.apple.com/kb/HT213488'
    label: af854a3a-2127-422b-91ae-364da2661108
tags:
  - nvd
epss: 0.03231
epssPercentile: 0.87752
ingestedAt: '2026-07-27T14:19:53.842Z'
---

## Overview

An issue was discovered in ncurses through v6.2-1. _nc_captoinfo in captoinfo.c has a heap-based buffer overflow.

## Affected

- `ncurses <= 6.2.1`
- `mac_os_x = 10.12.6`
- `macos = 11.7`
- `macos = 13.0`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.