# CVE-2021-34121: htmldoc: An Out of Bounds flaw was discovered in htmodoc 1.9.12 in function parse_tree() in toc.cxx, this possibly leads to me...

CVE-2021-34121 is fixed in 2 products on 1 platform, first by htmldoc 1.9.2-1ubuntu0.2+esm1, released July 18, 2023. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2021-34121
- Priority: High
- CVSS: 7.8 (high)
- EPSS: 0.0034
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Jul 18, 2023

## Description

An Out of Bounds flaw was discovered in htmodoc 1.9.12 in function parse_tree() in toc.cxx, this possibly leads to memory layout information leaking in the data. This might be used in a chain of vulnerability in order to reach code execution.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | htmldoc Debian 12.15 (bookworm) | 1.9.13-1 | [DEBIAN-CVE-2021-34121](https://patchblox.com/security/data/fix/linux/debian-cve-2021-34121.md) | Jul 18, 2023 |
| Linux | htmldoc Debian 13.5 (trixie) | 1.9.13-1 | [DEBIAN-CVE-2021-34121](https://patchblox.com/security/data/fix/linux/debian-cve-2021-34121.md) | Jul 18, 2023 |
| Linux | htmldoc Debian 14 | 1.9.13-1 | [DEBIAN-CVE-2021-34121](https://patchblox.com/security/data/fix/linux/debian-cve-2021-34121.md) | Jul 18, 2023 |
| Linux | htmldoc Ubuntu 18.04.6 LTS (bionic) | 1.9.2-1ubuntu0.2+esm1 | [htmldoc 1.9.2-1ubuntu0.2+esm1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-htmldoc-1.9.2-1ubuntu0.2-esm1.md) | Jul 18, 2023 |
| Linux | htmldoc Ubuntu 20.04 LTS (focal) | 1.9.7-1ubuntu0.3+esm1 | [htmldoc 1.9.7-1ubuntu0.3+esm1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-htmldoc-1.9.7-1ubuntu0.3-esm1.md) | Jul 18, 2023 |
| Linux | htmldoc-common Ubuntu 18.04.6 LTS (bionic) | 1.9.2-1ubuntu0.2+esm1 | [htmldoc-common 1.9.2-1ubuntu0.2+esm1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-htmldoc-common-1.9.2-1ubuntu0.2-esm1.md) | Jul 18, 2023 |
| Linux | htmldoc-common Ubuntu 20.04 LTS (focal) | 1.9.7-1ubuntu0.3+esm1 | [htmldoc-common 1.9.7-1ubuntu0.3+esm1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-htmldoc-common-1.9.7-1ubuntu0.3-esm1.md) | Jul 18, 2023 |

---

Data as of 2026-11-08T19:12:23Z 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 Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

Free to use with attribution: show "Data: Patchblox Patch Radar" with a link to https://patchblox.com/security/patch-radar. Terms, including what needs a written agreement: https://patchblox.com/security/patch-radar/use-the-data

Product names, logos and trademarks shown on Patch Radar belong to their respective owners. They are used only to identify the software each security fix applies to and to help readers find their platform. Their use does not imply any affiliation with, or endorsement by, those owners, and Patchblox is not affiliated with any of them.