CVE-2025-13742
CVE-2025-13742 is a CWE-116 vulnerability in pretix. O3 Security confirms whether CVE-2025-13742 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Limited HTML injection in emails
Real-World Exposure
pretix🐍pretix🐍pretixReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects PyPI packages — download data is not available via public APIs for these ecosystems.
Description
Emails sent by pretix can utilize placeholders that will be filled with customer data. For example, when {name} is used in an email template, it will be replaced with the buyer's name for the final email. If the name of the attendee contained HTML or Markdown formatting, this was rendered as HTML in the resulting email. This way, a user could inject links or other formatted text through a maliciously formatted name. Since pretix applies a strict allow list approach to allowed HTML tags, this could not be abused for XSS or similarly dangerous attack chains. However, it can be used to manipulate emails in a way that makes user-provided content appear in a trustworthy and credible way, which can be abused for phishing.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | pretix | ≥ 1.0.0&&< 2025.7.3 | 2025.7.3 |
| 🐍PyPI | pretix | ≥ 2025.8.0&&< 2025.8.2 | 2025.8.2 |
| 🐍PyPI | pretix | ≥ 2025.9.0&&< 2025.9.2 | 2025.9.2 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for pretix. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update pretix to 2025.7.3 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2025-13742 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2025-13742 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2025-13742. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2025-13742 in your dependencies?
O3 detects CVE-2025-13742 across PyPI dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.