# CVE-2017-18926: libraptor2-0: raptor_xml_writer_start_element_common in raptor_xml_writer.c in Raptor RDFSyntax Library 2.0.15 miscalculates the ma...

CVE-2017-18926 is fixed in 4 products on 1 platform, first by libraptor2-0 2.0.14-1ubuntu0.18.04.1, released November 6, 2020. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2017-18926
- Priority: High
- CVSS: 7.1 (Medium)
- EPSS: 0.0312
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Nov 6, 2020

## Description

raptor_xml_writer_start_element_common in raptor_xml_writer.c in Raptor RDFSyntax Library 2.0.15 miscalculates the maximum nspace declarations for theXML writer, leading to heap-based buffer overflows (sometimes seen inraptor_qname_format_as_xml).

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | libraptor2-0 Ubuntu 18.04.6 LTS (bionic) | 2.0.14-1ubuntu0.18.04.1 | [libraptor2-0 2.0.14-1ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-libraptor2-0-2.0.14-1ubuntu0.18.04.1.md) | Nov 6, 2020 |
| Linux | libraptor2-0 Ubuntu 20.04 LTS (focal) | 2.0.15-0ubuntu1.20.04.1 | [libraptor2-0 2.0.15-0ubuntu1.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-libraptor2-0-2.0.15-0ubuntu1.20.04.1.md) | Nov 6, 2020 |
| Linux | libraptor2-0 Ubuntu 22.04.1 LTS (jammy) | 2.0.15-0ubuntu2 | [libraptor2-0 2.0.15-0ubuntu2](https://patchblox.com/security/data/fix/linux/ubuntu-jammy-libraptor2-0-2.0.15-0ubuntu2.md) | Nov 6, 2020 |
| Linux | libraptor2-0 Ubuntu 24.10 (oracular) | 2.0.15-0ubuntu2 | [libraptor2-0 2.0.15-0ubuntu2](https://patchblox.com/security/data/fix/linux/ubuntu-oracular-libraptor2-0-2.0.15-0ubuntu2.md) | Jan 16, 2026 |
| Linux | libraptor2-0 Ubuntu 25.04 (plucky) | 2.0.15-0ubuntu2 | [libraptor2-0 2.0.15-0ubuntu2](https://patchblox.com/security/data/fix/linux/ubuntu-plucky-libraptor2-0-2.0.15-0ubuntu2.md) | Jan 16, 2026 |
| Linux | raptor2 RHEL 8 | 0:2.0.15-16.el8 | [RHSA-2021:1842](https://patchblox.com/security/data/fix/linux/rhsa-2021-1842.md) | May 18, 2021 |
| Linux | raptor2 ol 8 | 0:2.0.15-16.el8 | [ELSA-2021-1842](https://patchblox.com/security/data/fix/linux/elsa-2021-1842.md) | May 25, 2021 |
| Linux | raptor2-devel RHEL 8 | 0:2.0.15-16.el8 | [RHSA-2021:1842](https://patchblox.com/security/data/fix/linux/rhsa-2021-1842.md) | May 18, 2021 |
| Linux | raptor2-devel ol 8 | 0:2.0.15-16.el8 | [ELSA-2021-1842](https://patchblox.com/security/data/fix/linux/elsa-2021-1842.md) | May 25, 2021 |
| Linux | raptor2-utils Ubuntu 18.04.6 LTS (bionic) | 2.0.14-1ubuntu0.18.04.1 | [raptor2-utils 2.0.14-1ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-raptor2-utils-2.0.14-1ubuntu0.18.04.1.md) | Nov 6, 2020 |
| Linux | raptor2-utils Ubuntu 20.04 LTS (focal) | 2.0.15-0ubuntu1.20.04.1 | [raptor2-utils 2.0.15-0ubuntu1.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-raptor2-utils-2.0.15-0ubuntu1.20.04.1.md) | Nov 6, 2020 |
| Linux | raptor2-utils Ubuntu 22.04.1 LTS (jammy) | 2.0.15-0ubuntu2 | [raptor2-utils 2.0.15-0ubuntu2](https://patchblox.com/security/data/fix/linux/ubuntu-jammy-raptor2-utils-2.0.15-0ubuntu2.md) | Nov 6, 2020 |
| Linux | raptor2-utils Ubuntu 24.10 (oracular) | 2.0.15-0ubuntu2 | [raptor2-utils 2.0.15-0ubuntu2](https://patchblox.com/security/data/fix/linux/ubuntu-oracular-raptor2-utils-2.0.15-0ubuntu2.md) | Jan 16, 2026 |
| Linux | raptor2-utils Ubuntu 25.04 (plucky) | 2.0.15-0ubuntu2 | [raptor2-utils 2.0.15-0ubuntu2](https://patchblox.com/security/data/fix/linux/ubuntu-plucky-raptor2-utils-2.0.15-0ubuntu2.md) | Jan 16, 2026 |

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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