# CVE-2026-59924: python-mistune: This update for python-mistune fixes the following issues  - CVE-2026-59922: quadratic-time parsing on long runs of s...

CVE-2026-59924 is fixed in 3 products on 1 platform, first by SUSE-SU-2026:22655-1, released July 14, 2026. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2026-59924
- Priority: High
- CVSS: n/a (important)
- EPSS: 0.0046
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Jul 14, 2026

## Description

This update for python-mistune fixes the following issues  - CVE-2026-59922: quadratic-time parsing on long runs of some markers in `formatting.py` can lead to DoS (bsc#1271117). - CVE-2026-59923: `HTMLRenderer.safe_url()` does not block percent-encoded javascript URIs and allows for XSS   (bsc#1271119). - CVE-2026-59924: improper processing of user-supplied include paths in `Include.parse()` can lead to path traversal   and arbitrary file reads (bsc#1271121). - CVE-2026-59925: quadratic-time parsing on long runs of some emphasis pairs in `inline_parser` can lead to DoS   (bsc#1271125). - CVE-2026-59926: improper escaping in `render_admonition()` can lead to atribute injection and XSS (bsc#1271127). - CVE-2026-59927: uncontrolled recursion when processing two markdown files that include each other can lead to a DoS    (bsc#1271128). - CVE-2026-59928: quadratic-time parsing on long lists of repeated reference-link definitions in `block_parser` can   lead to DoS (bsc#1271131). - CVE-2026-59929: HARMFUL_PROTOCOLS list misses legacy and chained schemes and allow arbitrary script execution in   user agents (bsc#1271132). - CVE-2026-59930: the `toc` plugin and `TableOfContents` directive generate heading IDs with predictable values and   allow for collisions with attacker-controlled `id="toc_N"` content (bsc#1271082).

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | python-mistune Fedora 43 | 3.3.4-1.fc43 | [FEDORA-2026-340793A2F1](https://patchblox.com/security/data/fix/linux/fedora-2026-340793a2f1.md) | Nov 7, 2026 |
| Linux | python-mistune opensuse-leap 16.0 | 3.1.3-160000.5.1 | [OPENSUSE-SU-2026:21339-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2026-21339-1.md) | Jul 14, 2026 |
| Linux | python-mistune sles 16.0 | 3.1.3-160000.5.1 | [SUSE-SU-2026:22655-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-22655-1.md) | Jul 14, 2026 |
| Linux | python-mistune-doc Fedora 43 | 3.3.4-1.fc43 | [FEDORA-2026-340793A2F1](https://patchblox.com/security/data/fix/linux/fedora-2026-340793a2f1.md) | Nov 7, 2026 |
| Linux | python3-mistune Fedora 43 | 3.3.4-1.fc43 | [FEDORA-2026-340793A2F1](https://patchblox.com/security/data/fix/linux/fedora-2026-340793a2f1.md) | Nov 7, 2026 |

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Data as of 2026-11-09T01:18:40Z 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

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