CVE-2026-41426 json
pretalx: Email injection via unescaped user-controlled placeholders in pretalx mail templates
published 2026-04-18 6 mo ago modified 2026-06-17 4 mo ago also EUVD-2026-25616 , GHSA-jm8c-9f3j-4378 , PYSEC-2026-109
- cvss
- 6.1
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.2%
- EPSS 0.2% chance of exploitation in 30 days, percentile 4%
- public exploits
- 0
- none known
Summary
pretalx is a conference planning tool. Prior to 2026.1.0, an unauthenticated attacker can send arbitrary HTML-rendered emails from a pretalx instance's configured sender address by embedding malformed HTML or markdown link syntax in a user-controlled template placeholder such as the account display name. The most direct vector is the password-reset flow: the attacker registers an account with a malicious name, enters the victim's email address, and triggers a password reset. The resulting email is delivered from the event's legitimate sender address and passes SPF/DKIM/DMARC validation, making it a ready-made phishing vector. This vulnerability is fixed in 2026.1.0.
Patch / fix
- pypi pretalx 2026.1.0
- pretalx pretalx 2026.1.0
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 6 mo ago
Exploit prediction
0.15% chance of exploitation in the next 30 days, higher than 4% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 6.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N |
| GitHub | 3.1 | 6.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N |
| OSV | 3.1 | 6.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| pypi | pretalx | <2026.1.0 |
2026.1.0 |
Affected products
- pretalx pretalx
Classification
References
-
github.com
/pretalx/pretalx/security/advisories/GHSA-jm8c-9f3j-4378
web, vendor-advisory, advisory
-
nvd.nist.gov
/vuln/detail/CVE-2026-41426
advisory
-
github.com
/pretalx/pretalx
package
-
github.com
/pypa/advisory-database/tree/main/vulns/pretalx/PYSEC-2026-109.yaml
web
Sources
- CVE List CVE-2026-41426
- GitHub Advisory GHSA-jm8c-9f3j-4378
- NVD CVE-2026-41426
- OSV PYSEC-2026-109
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.
CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.