# mdex (Hex) vulnerabilities

6 known vulnerabilities (1 high, 4 medium, 1 low), with the versions each affects and the releases that fix them.

## At a glance

- Latest release: not known (cve.now hasn't read this package's releases)
- Newest unaffected release: not known without release data
- Registry: https://hex.pm/packages/mdex

## Advisories (6)

### [CVE-2026-53426](https://cve.now/CVE-2026-53426): Atom-table exhaustion denial-of-service via JSON parse\_document in MDEx

- Severity: High 8.2
- Published: Jun 29, 2026
- Affected: from 0.4.3, fixed in 0.13.2; from 0.4.3, fixed in 0.13.2.

### [CVE-2026-54889](https://cve.now/CVE-2026-54889): Unsanitized URL schemes in MDEx Quill Delta output allow javascript: injection (XSS)

- Severity: Medium 5.1
- Published: Jun 29, 2026
- Affected: from 0.8.3, fixed in 0.13.2; from 0.8.3, fixed in 0.13.2.

### [CVE-2026-54888](https://cve.now/CVE-2026-54888): Uncontrolled recursion over deeply nested Markdown crashes the BEAM in mdex

- Severity: Medium 6.9
- Published: Jun 29, 2026
- Affected: from 0.3.0, fixed in 0.12.3; from 0.3.0, fixed in 0.12.3.

### [CVE-2026-53429](https://cve.now/CVE-2026-53429): Unbounded native memory leak in mdex escaped-tag rendering enables unauthenticated denial of service

- Severity: Medium 6.9
- Published: Jun 29, 2026
- Affected: from 0.11.0, fixed in 0.12.3; from 0.11.0, fixed in 0.12.3.

### [CVE-2026-53428](https://cve.now/CVE-2026-53428): Unbounded memory allocation in highlight\_lines range expansion in mdex

- Severity: Medium 6.9
- Published: Jun 29, 2026
- Affected: from 0.11.0, fixed in 0.12.3; from 0.11.0, fixed in 0.12.3.

### [CVE-2026-53427](https://cve.now/CVE-2026-53427): Cross-site scripting in MDEx via unescaped highlight\_lines\_class code-fence attribute

- Severity: Low 2.3
- Published: Jun 29, 2026
- Affected: from 0.11.3, fixed in 0.12.3; from 0.11.3, fixed in 0.12.3.

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