# CVE-2021-31870: libklibc: An issue was discovered in klibc before 2.0.9

CVE-2021-31870 is fixed in 2 products on 1 platform, first by klibc-utils 2.0.4-9ubuntu2.1, released April 29, 2021. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2021-31870
- Priority: Routine
- CVSS: n/a (Low)
- EPSS: 0.0208
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Apr 29, 2021

## Description

An issue was discovered in klibc before 2.0.9. Multiplication in the calloc() function may result in an integer overflow and a subsequent heap buffer overflow.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | klibc-utils Ubuntu 18.04.6 LTS (bionic) | 2.0.4-9ubuntu2.1 | [klibc-utils 2.0.4-9ubuntu2.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-klibc-utils-2.0.4-9ubuntu2.1.md) | Apr 29, 2021 |
| Linux | klibc-utils Ubuntu 20.04 LTS (focal) | 2.0.7-1ubuntu5.1 | [klibc-utils 2.0.7-1ubuntu5.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-klibc-utils-2.0.7-1ubuntu5.1.md) | Apr 29, 2021 |
| Linux | libklibc Ubuntu 18.04.6 LTS (bionic) | 2.0.4-9ubuntu2.1 | [libklibc 2.0.4-9ubuntu2.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-libklibc-2.0.4-9ubuntu2.1.md) | Apr 29, 2021 |
| Linux | libklibc Ubuntu 20.04 LTS (focal) | 2.0.7-1ubuntu5.1 | [libklibc 2.0.7-1ubuntu5.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-libklibc-2.0.7-1ubuntu5.1.md) | Apr 29, 2021 |

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