# CVE-2020-12663: python3-unbound: The unbound packages provide a validating, recursive, and caching DNS or DNSSEC resolver

CVE-2020-12663 is fixed in 9 products on 1 platform, first by libunbound2 1.6.7-1ubuntu2.3, released May 19, 2020. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2020-12663
- Priority: High
- CVSS: 7.5 (Important)
- EPSS: 0.0359
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: May 19, 2020

## Description

The unbound packages provide a validating, recursive, and caching DNS or DNSSEC resolver.   Security Fix(es):  * unbound: amplification of an incoming query into a large number of queries directed to a target (CVE-2020-12662)  * unbound: infinite loop via malformed DNS answers received from upstream servers (CVE-2020-12663)  For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | libunbound2 Ubuntu 18.04.6 LTS (bionic) | 1.6.7-1ubuntu2.3 | [libunbound2 1.6.7-1ubuntu2.3](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-libunbound2-1.6.7-1ubuntu2.3.md) | May 19, 2020 |
| Linux | libunbound8 Ubuntu 20.04 LTS (focal) | 1.9.4-2ubuntu1.1 | [libunbound8 1.9.4-2ubuntu1.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-libunbound8-1.9.4-2ubuntu1.1.md) | May 19, 2020 |
| Linux | python-unbound Ubuntu 18.04.6 LTS (bionic) | 1.6.7-1ubuntu2.3 | [python-unbound 1.6.7-1ubuntu2.3](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-python-unbound-1.6.7-1ubuntu2.3.md) | May 19, 2020 |
| Linux | python-unbound Ubuntu 20.04 LTS (focal) | 1.9.4-2ubuntu1.1 | [python-unbound 1.9.4-2ubuntu1.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-python-unbound-1.9.4-2ubuntu1.1.md) | May 19, 2020 |
| Linux | python3-unbound RHEL 8 | 0:1.7.3-11.el8_2 | [RHSA-2020:2416](https://patchblox.com/security/data/fix/linux/rhsa-2020-2416.md) | Jun 8, 2020 |
| Linux | python3-unbound Ubuntu 18.04.6 LTS (bionic) | 1.6.7-1ubuntu2.3 | [python3-unbound 1.6.7-1ubuntu2.3](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-python3-unbound-1.6.7-1ubuntu2.3.md) | May 19, 2020 |
| Linux | python3-unbound Ubuntu 20.04 LTS (focal) | 1.9.4-2ubuntu1.1 | [python3-unbound 1.9.4-2ubuntu1.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-python3-unbound-1.9.4-2ubuntu1.1.md) | May 19, 2020 |
| Linux | python3-unbound ol 8 | 0:1.7.3-11.el8_2 | [ELSA-2020-2416](https://patchblox.com/security/data/fix/linux/elsa-2020-2416.md) | Jun 8, 2020 |
| Linux | unbound RHEL 8 | 0:1.7.3-11.el8_2 | [RHSA-2020:2416](https://patchblox.com/security/data/fix/linux/rhsa-2020-2416.md) | Jun 8, 2020 |
| Linux | unbound Ubuntu 18.04.6 LTS (bionic) | 1.6.7-1ubuntu2.3 | [unbound 1.6.7-1ubuntu2.3](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-unbound-1.6.7-1ubuntu2.3.md) | May 19, 2020 |
| Linux | unbound Ubuntu 20.04 LTS (focal) | 1.9.4-2ubuntu1.1 | [unbound 1.9.4-2ubuntu1.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-unbound-1.9.4-2ubuntu1.1.md) | May 19, 2020 |
| Linux | unbound ol 8 | 0:1.7.3-11.el8_2 | [ELSA-2020-2416](https://patchblox.com/security/data/fix/linux/elsa-2020-2416.md) | Jun 8, 2020 |
| Linux | unbound-anchor Ubuntu 18.04.6 LTS (bionic) | 1.6.7-1ubuntu2.3 | [unbound-anchor 1.6.7-1ubuntu2.3](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-unbound-anchor-1.6.7-1ubuntu2.3.md) | May 19, 2020 |
| Linux | unbound-anchor Ubuntu 20.04 LTS (focal) | 1.9.4-2ubuntu1.1 | [unbound-anchor 1.9.4-2ubuntu1.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-unbound-anchor-1.9.4-2ubuntu1.1.md) | May 19, 2020 |
| Linux | unbound-devel RHEL 8 | 0:1.7.3-11.el8_2 | [RHSA-2020:2416](https://patchblox.com/security/data/fix/linux/rhsa-2020-2416.md) | Jun 8, 2020 |
| Linux | unbound-devel ol 8 | 0:1.7.3-11.el8_2 | [ELSA-2020-2416](https://patchblox.com/security/data/fix/linux/elsa-2020-2416.md) | Jun 8, 2020 |
| Linux | unbound-host Ubuntu 18.04.6 LTS (bionic) | 1.6.7-1ubuntu2.3 | [unbound-host 1.6.7-1ubuntu2.3](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-unbound-host-1.6.7-1ubuntu2.3.md) | May 19, 2020 |
| Linux | unbound-host Ubuntu 20.04 LTS (focal) | 1.9.4-2ubuntu1.1 | [unbound-host 1.9.4-2ubuntu1.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-unbound-host-1.9.4-2ubuntu1.1.md) | May 19, 2020 |
| Linux | unbound-libs RHEL 8 | 0:1.7.3-11.el8_2 | [RHSA-2020:2416](https://patchblox.com/security/data/fix/linux/rhsa-2020-2416.md) | Jun 8, 2020 |
| Linux | unbound-libs ol 8 | 0:1.7.3-11.el8_2 | [ELSA-2020-2416](https://patchblox.com/security/data/fix/linux/elsa-2020-2416.md) | Jun 8, 2020 |

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