# CVE-2019-25035: python3-unbound: The unbound packages provide a validating, recursive, and caching DNS or DNSSEC resolver

CVE-2019-25035 is fixed in 9 products on 1 platform, first by libunbound2 1.6.7-1ubuntu2.4, released April 26, 2021. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2019-25035
- Priority: High
- CVSS: 9.8 (Moderate)
- EPSS: 0.0288
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Apr 26, 2021

## Description

The unbound packages provide a validating, recursive, and caching DNS or DNSSEC resolver.   Security Fix(es):  * unbound: integer overflow in the regional allocator via regional_alloc (CVE-2019-25032)  * unbound: integer overflow in sldns_str2wire_dname_buf_origin can lead to an out-of-bounds write (CVE-2019-25034)  * unbound: out-of-bounds write in sldns_bget_token_par (CVE-2019-25035)  * unbound: assertion failure and denial of service in synth_cname (CVE-2019-25036)  * unbound: assertion failure and denial of service in dname_pkt_copy via an invalid packet (CVE-2019-25037)  * unbound: integer overflow in a size calculation in dnscrypt/dnscrypt.c (CVE-2019-25038)  * unbound: integer overflow in a size calculation in respip/respip.c (CVE-2019-25039)  * unbound: infinite loop via a compressed name in dname_pkt_copy (CVE-2019-25040)  * unbound: assertion failure via a compressed name in dname_pkt_copy (CVE-2019-25041)  * unbound: out-of-bounds write via a compressed name in rdata_copy (CVE-2019-25042)  * unbound: symbolic link traversal when writing PID file (CVE-2020-28935)  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.  Additional Changes:  For detailed information on changes in this release, see the Red Hat Enterprise Linux 8.4 Release Notes linked from the References section.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | libunbound2 Ubuntu 18.04.6 LTS (bionic) | 1.6.7-1ubuntu2.4 | [libunbound2 1.6.7-1ubuntu2.4](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-libunbound2-1.6.7-1ubuntu2.4.md) | Apr 26, 2021 |
| Linux | libunbound8 Ubuntu 20.04 LTS (focal) | 1.9.4-2ubuntu1.2 | [libunbound8 1.9.4-2ubuntu1.2](https://patchblox.com/security/data/fix/linux/ubuntu-focal-libunbound8-1.9.4-2ubuntu1.2.md) | Apr 26, 2021 |
| Linux | python-unbound Ubuntu 18.04.6 LTS (bionic) | 1.6.7-1ubuntu2.4 | [python-unbound 1.6.7-1ubuntu2.4](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-python-unbound-1.6.7-1ubuntu2.4.md) | Apr 26, 2021 |
| Linux | python-unbound Ubuntu 20.04 LTS (focal) | 1.9.4-2ubuntu1.2 | [python-unbound 1.9.4-2ubuntu1.2](https://patchblox.com/security/data/fix/linux/ubuntu-focal-python-unbound-1.9.4-2ubuntu1.2.md) | Apr 26, 2021 |
| Linux | python3-unbound RHEL 8 | 0:1.7.3-15.el8 | [RHSA-2021:1853](https://patchblox.com/security/data/fix/linux/rhsa-2021-1853.md) | May 18, 2021 |
| Linux | python3-unbound Ubuntu 18.04.6 LTS (bionic) | 1.6.7-1ubuntu2.4 | [python3-unbound 1.6.7-1ubuntu2.4](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-python3-unbound-1.6.7-1ubuntu2.4.md) | Apr 26, 2021 |
| Linux | python3-unbound Ubuntu 20.04 LTS (focal) | 1.9.4-2ubuntu1.2 | [python3-unbound 1.9.4-2ubuntu1.2](https://patchblox.com/security/data/fix/linux/ubuntu-focal-python3-unbound-1.9.4-2ubuntu1.2.md) | Apr 26, 2021 |
| Linux | python3-unbound ol 8 | 0:1.7.3-15.el8 | [ELSA-2021-1853](https://patchblox.com/security/data/fix/linux/elsa-2021-1853.md) | May 25, 2021 |
| Linux | unbound RHEL 8 | 0:1.7.3-15.el8 | [RHSA-2021:1853](https://patchblox.com/security/data/fix/linux/rhsa-2021-1853.md) | May 18, 2021 |
| Linux | unbound Ubuntu 18.04.6 LTS (bionic) | 1.6.7-1ubuntu2.4 | [unbound 1.6.7-1ubuntu2.4](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-unbound-1.6.7-1ubuntu2.4.md) | Apr 26, 2021 |
| Linux | unbound Ubuntu 20.04 LTS (focal) | 1.9.4-2ubuntu1.2 | [unbound 1.9.4-2ubuntu1.2](https://patchblox.com/security/data/fix/linux/ubuntu-focal-unbound-1.9.4-2ubuntu1.2.md) | Apr 26, 2021 |
| Linux | unbound ol 8 | 0:1.7.3-15.el8 | [ELSA-2021-1853](https://patchblox.com/security/data/fix/linux/elsa-2021-1853.md) | May 25, 2021 |
| Linux | unbound-anchor Ubuntu 18.04.6 LTS (bionic) | 1.6.7-1ubuntu2.4 | [unbound-anchor 1.6.7-1ubuntu2.4](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-unbound-anchor-1.6.7-1ubuntu2.4.md) | Apr 26, 2021 |
| Linux | unbound-anchor Ubuntu 20.04 LTS (focal) | 1.9.4-2ubuntu1.2 | [unbound-anchor 1.9.4-2ubuntu1.2](https://patchblox.com/security/data/fix/linux/ubuntu-focal-unbound-anchor-1.9.4-2ubuntu1.2.md) | Apr 26, 2021 |
| Linux | unbound-devel RHEL 8 | 0:1.7.3-15.el8 | [RHSA-2021:1853](https://patchblox.com/security/data/fix/linux/rhsa-2021-1853.md) | May 18, 2021 |
| Linux | unbound-devel ol 8 | 0:1.7.3-15.el8 | [ELSA-2021-1853](https://patchblox.com/security/data/fix/linux/elsa-2021-1853.md) | May 25, 2021 |
| Linux | unbound-host Ubuntu 18.04.6 LTS (bionic) | 1.6.7-1ubuntu2.4 | [unbound-host 1.6.7-1ubuntu2.4](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-unbound-host-1.6.7-1ubuntu2.4.md) | Apr 26, 2021 |
| Linux | unbound-host Ubuntu 20.04 LTS (focal) | 1.9.4-2ubuntu1.2 | [unbound-host 1.9.4-2ubuntu1.2](https://patchblox.com/security/data/fix/linux/ubuntu-focal-unbound-host-1.9.4-2ubuntu1.2.md) | Apr 26, 2021 |
| Linux | unbound-libs RHEL 8 | 0:1.7.3-15.el8 | [RHSA-2021:1853](https://patchblox.com/security/data/fix/linux/rhsa-2021-1853.md) | May 18, 2021 |
| Linux | unbound-libs ol 8 | 0:1.7.3-15.el8 | [ELSA-2021-1853](https://patchblox.com/security/data/fix/linux/elsa-2021-1853.md) | May 25, 2021 |

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Data as of 2026-11-07T12:40:37Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo
