CVE-2026-2415 — pretix
Fix: pretix/pretix@ba11d24CVE-2026-2415 is a CWE-627 vulnerability in pretix. A fix is available for pretix — see the affected versions and patch details below.
Unsafe variable evaluation in email templates
Exploitation Status
No confirmed exploitation observed yet
- A successful exploit gives an attacker total control of the affected component, not partial access.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-2415.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
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. This mechanism contained two security-relevant bugs:
It was possible to exfiltrate information about the pretix system through specially crafted placeholder names such as {{event.init.code.co_filename}}. This way, an attacker with the ability to control email templates (usually every user of the pretix backend) could retrieve sensitive information from the system configuration, including even database passwords or API keys. pretix does include mechanisms to prevent the usage of such malicious placeholders, however due to a mistake in the code, they were not fully effective for the email subject.
Placeholders in subjects and plain text bodies of emails were wrongfully evaluated twice. Therefore, if the first evaluation of a placeholder again contains a placeholder, this second placeholder was rendered. This allows the rendering of placeholders controlled by the ticket buyer, and therefore the exploitation of the first issue as a ticket buyer. Luckily, the only buyer-controlled placeholder available in pretix by default (that is not validated in a way that prevents the issue) is {invoice_company}, which is very unusual (but not impossible) to be contained in an email subject template. In addition to broadening the attack surface of the first issue, this could theoretically also leak information about an order to one of the attendees within that order. However, we also consider this scenario very unlikely under typical conditions.
Out of caution, we recommend that you rotate all passwords and API keys contained in your pretix.cfg https://docs.pretix.eu/self-hosting/config/ file.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | pretix | ≥ 2026.1.0&&< 2026.1.1 | 2026.1.1pip install --upgrade 'pretix==2026.1.1' |
| 🐍PyPI | pretix | ≥ 2025.10.0&&< 2025.10.2 | 2025.10.2pip install --upgrade 'pretix==2025.10.2' |
| 🐍PyPI | pretix | all versions | 2025.9.4pip install --upgrade 'pretix==2025.9.4' |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for pretix, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update pretix to 2026.1.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-2415 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 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2026-2415 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2026-2415. 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-2026-2415 in your dependencies?
O3 Security finds CVE-2026-2415 across PyPI dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.