# CVE-2021-39537: libncurses6: An issue was discovered in ncurses through v6.2-1

CVE-2021-39537 is fixed in 35 products on 1 platform, first by ALAS2023-2023-023, released February 17, 2023. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2021-39537
- Priority: Routine
- CVSS: n/a (Negligible)
- EPSS: 0.0324
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Sep 20, 2021

## Description

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

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | lib32ncurses5 Ubuntu 18.04.6 LTS (bionic) | 6.1-1ubuntu1.18.04.1 | [lib32ncurses5 6.1-1ubuntu1.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-lib32ncurses5-6.1-1ubuntu1.18.04.1.md) | Apr 13, 2023 |
| Linux | lib32ncurses6 Ubuntu 20.04 LTS (focal) | 6.2-0ubuntu2.1 | [lib32ncurses6 6.2-0ubuntu2.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-lib32ncurses6-6.2-0ubuntu2.1.md) | Apr 13, 2023 |
| Linux | lib32ncursesw5 Ubuntu 18.04.6 LTS (bionic) | 6.1-1ubuntu1.18.04.1 | [lib32ncursesw5 6.1-1ubuntu1.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-lib32ncursesw5-6.1-1ubuntu1.18.04.1.md) | Apr 13, 2023 |
| Linux | lib32ncursesw6 Ubuntu 20.04 LTS (focal) | 6.2-0ubuntu2.1 | [lib32ncursesw6 6.2-0ubuntu2.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-lib32ncursesw6-6.2-0ubuntu2.1.md) | Apr 13, 2023 |
| Linux | lib32tinfo5 Ubuntu 18.04.6 LTS (bionic) | 6.1-1ubuntu1.18.04.1 | [lib32tinfo5 6.1-1ubuntu1.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-lib32tinfo5-6.1-1ubuntu1.18.04.1.md) | Apr 13, 2023 |
| Linux | lib32tinfo6 Ubuntu 20.04 LTS (focal) | 6.2-0ubuntu2.1 | [lib32tinfo6 6.2-0ubuntu2.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-lib32tinfo6-6.2-0ubuntu2.1.md) | Apr 13, 2023 |
| Linux | lib64ncurses5 Ubuntu 18.04.6 LTS (bionic) | 6.1-1ubuntu1.18.04.1 | [lib64ncurses5 6.1-1ubuntu1.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-lib64ncurses5-6.1-1ubuntu1.18.04.1.md) | Apr 13, 2023 |
| Linux | lib64ncurses6 Ubuntu 20.04 LTS (focal) | 6.2-0ubuntu2.1 | [lib64ncurses6 6.2-0ubuntu2.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-lib64ncurses6-6.2-0ubuntu2.1.md) | Apr 13, 2023 |
| Linux | lib64ncursesw6 Ubuntu 20.04 LTS (focal) | 6.2-0ubuntu2.1 | [lib64ncursesw6 6.2-0ubuntu2.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-lib64ncursesw6-6.2-0ubuntu2.1.md) | Apr 13, 2023 |
| Linux | lib64tinfo5 Ubuntu 18.04.6 LTS (bionic) | 6.1-1ubuntu1.18.04.1 | [lib64tinfo5 6.1-1ubuntu1.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-lib64tinfo5-6.1-1ubuntu1.18.04.1.md) | Apr 13, 2023 |
| Linux | lib64tinfo6 Ubuntu 20.04 LTS (focal) | 6.2-0ubuntu2.1 | [lib64tinfo6 6.2-0ubuntu2.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-lib64tinfo6-6.2-0ubuntu2.1.md) | Apr 13, 2023 |
| Linux | libncurses5 Ubuntu 18.04.6 LTS (bionic) | 6.1-1ubuntu1.18.04.1 | [libncurses5 6.1-1ubuntu1.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-libncurses5-6.1-1ubuntu1.18.04.1.md) | Apr 13, 2023 |
| Linux | libncurses5 Ubuntu 20.04 LTS (focal) | 6.2-0ubuntu2.1 | [libncurses5 6.2-0ubuntu2.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-libncurses5-6.2-0ubuntu2.1.md) | Apr 13, 2023 |
| Linux | libncurses6 Ubuntu 20.04 LTS (focal) | 6.2-0ubuntu2.1 | [libncurses6 6.2-0ubuntu2.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-libncurses6-6.2-0ubuntu2.1.md) | Apr 13, 2023 |
| Linux | libncursesw5 Ubuntu 18.04.6 LTS (bionic) | 6.1-1ubuntu1.18.04.1 | [libncursesw5 6.1-1ubuntu1.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-libncursesw5-6.1-1ubuntu1.18.04.1.md) | Apr 13, 2023 |
| Linux | libncursesw5 Ubuntu 20.04 LTS (focal) | 6.2-0ubuntu2.1 | [libncursesw5 6.2-0ubuntu2.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-libncursesw5-6.2-0ubuntu2.1.md) | Apr 13, 2023 |
| Linux | libncursesw6 Ubuntu 20.04 LTS (focal) | 6.2-0ubuntu2.1 | [libncursesw6 6.2-0ubuntu2.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-libncursesw6-6.2-0ubuntu2.1.md) | Apr 13, 2023 |
| Linux | libtinfo5 Ubuntu 18.04.6 LTS (bionic) | 6.1-1ubuntu1.18.04.1 | [libtinfo5 6.1-1ubuntu1.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-libtinfo5-6.1-1ubuntu1.18.04.1.md) | Apr 13, 2023 |
| Linux | libtinfo5 Ubuntu 20.04 LTS (focal) | 6.2-0ubuntu2.1 | [libtinfo5 6.2-0ubuntu2.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-libtinfo5-6.2-0ubuntu2.1.md) | Apr 13, 2023 |
| Linux | libtinfo6 Ubuntu 20.04 LTS (focal) | 6.2-0ubuntu2.1 | [libtinfo6 6.2-0ubuntu2.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-libtinfo6-6.2-0ubuntu2.1.md) | Apr 13, 2023 |
| Linux | libx32ncurses5 Ubuntu 18.04.6 LTS (bionic) | 6.1-1ubuntu1.18.04.1 | [libx32ncurses5 6.1-1ubuntu1.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-libx32ncurses5-6.1-1ubuntu1.18.04.1.md) | Apr 13, 2023 |
| Linux | libx32ncursesw5 Ubuntu 18.04.6 LTS (bionic) | 6.1-1ubuntu1.18.04.1 | [libx32ncursesw5 6.1-1ubuntu1.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-libx32ncursesw5-6.1-1ubuntu1.18.04.1.md) | Apr 13, 2023 |
| Linux | libx32tinfo5 Ubuntu 18.04.6 LTS (bionic) | 6.1-1ubuntu1.18.04.1 | [libx32tinfo5 6.1-1ubuntu1.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-libx32tinfo5-6.1-1ubuntu1.18.04.1.md) | Apr 13, 2023 |
| Linux | ncurses amzn 2023 | 6.2-4.20200222.amzn2023.0.3 | [ALAS2023-2023-023](https://patchblox.com/security/data/fix/linux/alas2023-2023-023.md) | Feb 17, 2023 |
| Linux | ncurses-base Ubuntu 18.04.6 LTS (bionic) | 6.1-1ubuntu1.18.04.1 | [ncurses-base 6.1-1ubuntu1.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-ncurses-base-6.1-1ubuntu1.18.04.1.md) | Apr 13, 2023 |
| Linux | ncurses-base Ubuntu 20.04 LTS (focal) | 6.2-0ubuntu2.1 | [ncurses-base 6.2-0ubuntu2.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-ncurses-base-6.2-0ubuntu2.1.md) | Apr 13, 2023 |
| Linux | ncurses-base amzn 2023 | 6.2-4.20200222.amzn2023.0.3 | [ALAS2023-2023-023](https://patchblox.com/security/data/fix/linux/alas2023-2023-023.md) | Feb 17, 2023 |
| Linux | ncurses-bin Ubuntu 18.04.6 LTS (bionic) | 6.1-1ubuntu1.18.04.1 | [ncurses-bin 6.1-1ubuntu1.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-ncurses-bin-6.1-1ubuntu1.18.04.1.md) | Apr 13, 2023 |
| Linux | ncurses-bin Ubuntu 20.04 LTS (focal) | 6.2-0ubuntu2.1 | [ncurses-bin 6.2-0ubuntu2.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-ncurses-bin-6.2-0ubuntu2.1.md) | Apr 13, 2023 |
| Linux | ncurses-c++-libs amzn 2023 | 6.2-4.20200222.amzn2023.0.3 | [ALAS2023-2023-023](https://patchblox.com/security/data/fix/linux/alas2023-2023-023.md) | Feb 17, 2023 |
| Linux | ncurses-c++-libs-debuginfo amzn 2023 | 6.2-4.20200222.amzn2023.0.3 | [ALAS2023-2023-023](https://patchblox.com/security/data/fix/linux/alas2023-2023-023.md) | Feb 17, 2023 |
| Linux | ncurses-compat-libs amzn 2023 | 6.2-4.20200222.amzn2023.0.3 | [ALAS2023-2023-023](https://patchblox.com/security/data/fix/linux/alas2023-2023-023.md) | Feb 17, 2023 |
| Linux | ncurses-compat-libs-debuginfo amzn 2023 | 6.2-4.20200222.amzn2023.0.3 | [ALAS2023-2023-023](https://patchblox.com/security/data/fix/linux/alas2023-2023-023.md) | Feb 17, 2023 |
| Linux | ncurses-debuginfo amzn 2023 | 6.2-4.20200222.amzn2023.0.3 | [ALAS2023-2023-023](https://patchblox.com/security/data/fix/linux/alas2023-2023-023.md) | Feb 17, 2023 |
| Linux | ncurses-debugsource amzn 2023 | 6.2-4.20200222.amzn2023.0.3 | [ALAS2023-2023-023](https://patchblox.com/security/data/fix/linux/alas2023-2023-023.md) | Feb 17, 2023 |
| Linux | ncurses-devel amzn 2023 | 6.2-4.20200222.amzn2023.0.3 | [ALAS2023-2023-023](https://patchblox.com/security/data/fix/linux/alas2023-2023-023.md) | Feb 17, 2023 |
| Linux | ncurses-examples Ubuntu 18.04.6 LTS (bionic) | 6.1-1ubuntu1.18.04.1 | [ncurses-examples 6.1-1ubuntu1.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-ncurses-examples-6.1-1ubuntu1.18.04.1.md) | Apr 13, 2023 |
| Linux | ncurses-examples Ubuntu 20.04 LTS (focal) | 6.2-0ubuntu2.1 | [ncurses-examples 6.2-0ubuntu2.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-ncurses-examples-6.2-0ubuntu2.1.md) | Apr 13, 2023 |
| Linux | ncurses-libs amzn 2023 | 6.2-4.20200222.amzn2023.0.3 | [ALAS2023-2023-023](https://patchblox.com/security/data/fix/linux/alas2023-2023-023.md) | Feb 17, 2023 |
| Linux | ncurses-libs-debuginfo amzn 2023 | 6.2-4.20200222.amzn2023.0.3 | [ALAS2023-2023-023](https://patchblox.com/security/data/fix/linux/alas2023-2023-023.md) | Feb 17, 2023 |
| Linux | ncurses-static amzn 2023 | 6.2-4.20200222.amzn2023.0.3 | [ALAS2023-2023-023](https://patchblox.com/security/data/fix/linux/alas2023-2023-023.md) | Feb 17, 2023 |
| Linux | ncurses-term Ubuntu 18.04.6 LTS (bionic) | 6.1-1ubuntu1.18.04.1 | [ncurses-term 6.1-1ubuntu1.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-ncurses-term-6.1-1ubuntu1.18.04.1.md) | Apr 13, 2023 |
| Linux | ncurses-term Ubuntu 20.04 LTS (focal) | 6.2-0ubuntu2.1 | [ncurses-term 6.2-0ubuntu2.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-ncurses-term-6.2-0ubuntu2.1.md) | Apr 13, 2023 |
| Linux | ncurses-term amzn 2023 | 6.2-4.20200222.amzn2023.0.3 | [ALAS2023-2023-023](https://patchblox.com/security/data/fix/linux/alas2023-2023-023.md) | Feb 17, 2023 |

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