CVE-2026-2415: Pretix Pretix Unsafely Evaluates Variables Vulnerability

HIGH
Advisory Identifier: GHSA-r8p8-qw9w-j9qv
CVSS 5.9
CWE-627
Published
Advisory Summary

CVE-2026-2415 is a HIGH (CVSS 5.9) pretix unsafely evaluates variables vulnerability (CWE-627: Dynamic Variable Evaluation) affecting Pretix libraries in the PyPI ecosystem. The issue involves pretix unsafely evaluates variables in emails. Remediation is available by upgrading affected packages to version 2026.1.1, 2025.10.2, 2025.9.4.

CVE-2026-2415 at a Glance

CVE Identifier CVE-2026-2415
GHSA Identifier GHSA-r8p8-qw9w-j9qv
Severity HIGH
CVSS v3.1 Base Score 5.9
CWE Classification CWE-627: Dynamic Variable Evaluation
Affected Product Pretix
Package Ecosystem PyPI
Published Date
Last Updated

Security Impact

CVSS: 5.9

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N).

Attack Vector Network (AV:N)
Attack Complexity High (AC:H)
Privileges Required None (PR:N)
User Interaction None (UI:N)
Scope Unchanged (S:U)
Confidentiality High (C:H)
Integrity None (I:N)
Availability None (A:N)

How to Fix CVE-2026-2415

To remediate this vulnerability, upgrade all affected Pretix dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

pretix fixed: 2026.1.1
pip install pretix>=2026.1.1
pretix fixed: 2025.10.2
pip install pretix>=2025.10.2
pretix fixed: 2025.9.4
pip install pretix>=2025.9.4
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release:

pip show pretix

How to Check if You Are Affected

To determine whether your Python environment is affected by CVE-2026-2415, inspect your installed packages using pip:

pip show pretix

Analyze the terminal output to locate any version of Pretix in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 2026.1.1), your application is affected.

Note: The pip show pretix command checks currently installed packages in your active Python environment.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-627: Dynamic Variable Evaluation, where in a language where the user can influence the name of a variable at runtime, if the variable names are not controlled, an attacker can read or write to arbitrary variables, or access arbitrary functions. In Pretix, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

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, pretix recommend that you rotate all passwords and API keys contained in your pretix.cfg https://docs.pretix.eu/self-hosting/config/  file.

CVE-2026-2415 Affected Pretix Versions

3 component(s)
Fixed Versions:
2026.1.12025.10.22025.9.4
Product / Package Ecosystem Affected Versions Fixed Version
pretix
PyPI
≥ 2026.1.0
< 2026.1.1
2026.1.1
pretix
PyPI
≥ 2025.10.0
< 2025.10.2
2025.10.2
pretix
PyPI
< 2025.9.4
2025.9.4

References

Frequently Asked Questions

What is CVE-2026-2415?
CVE-2026-2415 is a security vulnerability in Pretix involving pretix unsafely evaluates variables in emails under CWE-627: Dynamic Variable Evaluation.
Which Pretix versions are affected?
Affected versions include releases prior to 2026.1.1, 2025.10.2, 2025.9.4 across affected packages: pretix.
What version fixes CVE-2026-2415?
Upgrading to 2026.1.1, 2025.10.2, 2025.9.4 (or the latest patched release for your respective branch) resolves the vulnerability.
Is pretix affected?
Yes, pretix is affected in releases prior to 2026.1.1, 2025.10.2, 2025.9.4. Upgrade your dependency to 2026.1.1, 2025.10.2, 2025.9.4 or later.
What is the CVSS score of CVE-2026-2415?
CVE-2026-2415 has a CVSS v3.1 base score of 5.9 (HIGH) with vector string CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N.
What CWE is associated with CVE-2026-2415?
CVE-2026-2415 is classified under CWE-627: Dynamic Variable Evaluation (In a language where the user can influence the name of a variable at runtime, if the variable names are not controlled, an attacker can read or write to arbitrary variables, or access arbitrary functions.).
How can I check PyPI dependencies for CVE-2026-2415?
Run the dependency tree command: 'pip show pretix'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-r8p8-qw9w-j9qv",
  "modified" : "2026-03-13T16:04:01Z",
  "published" : "2026-02-16T12:30:25Z",
  "aliases" : [ "CVE-2026-2415" ],
  "summary" : "pretix unsafely evaluates variables in emails",
  "details" : "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:\n\n -  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.\n\n -  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.\n\nOut of caution, pretix recommend that you rotate all passwords and API keys contained in your pretix.cfg https://docs.pretix.eu/self-hosting/config/  file.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N"
  }, {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:N/AC:H/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:P/RE:L/U:Red"
  } ],
  "affected" : [ {
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      "ecosystem" : "PyPI",
      "name" : "pretix"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
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        "introduced" : "2026.1.0"
      }, {
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    } ]
  }, {
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    "ranges" : [ {
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  }, {
    "package" : {
      "ecosystem" : "PyPI",
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    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "2025.9.4"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-2415"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/pretix/pretix/commit/ba11d24f8dfa4e9d8f03493e56fd8b43983fe297"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/pretix/pretix/commit/c85afbc621b5f0b1afa618627c45f89323eb0154"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/pretix/pretix/commit/edac35ed4c5466eb63a202575c337d117ddf1c8e"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/pretix/pretix"
  }, {
    "type" : "WEB",
    "url" : "https://pretix.eu/about/en/blog/20260216-release-2026-1-1"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-627" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-02-18T21:44:45Z",
    "nvd_published_at" : "2026-02-16T11:15:56Z"
  }
}