Postorius is vulnerable to XSS
Postorius through 1.3.13 does not escape HTML in the message subject when rendering it in the Held messages pop-up, as exploited in the wild in May 2026.
Affected software
Click a technology to see all vulnerabilities affecting it.
| Platform | Package | Vulnerable versions | Fixed in |
|---|---|---|---|
| Python (PyPI) | postorius | <= 1.3.13 | no fix |
References
- https://nvd.nist.gov/vuln/detail/CVE-2026-44742
- https://gitlab.com/mailman/postorius
- https://gitlab.com/mailman/postorius/-/commit/c4706abd05ba6bcf472fc674b160d3a9d6a4868b
- https://gitlab.com/mailman/postorius/-/issues/620
- https://gitlab.com/mailman/postorius/-/merge_requests/972
- https://www.openwall.com/lists/oss-security/2026/05/07/3
- https://pypi.org/project/postorius
- https://github.com/advisories/GHSA-r7c9-7pjq-hmm8
- CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N- Weakness (CWE)
CWE-79- Platform
- Python (PyPI)
- Package
postorius- Disclosed
- 07.05.2026
- Updated
- 11.10.2026 14:17
Sources and licenses
OSV / GitHub Advisory Database - PYSEC-2026-2891 - PyPA Advisory Database; CC BY 4.0
OSV / GitHub Advisory Database - GHSA-r7c9-7pjq-hmm8 - CC BY 4.0
Vulnerability history: postorius
All published vulnerabilities of this package (Python (PyPI)), newest first. Shows whether this is a one-off slip or a package that needs watching.
- Total entries
- 2
- First → latest
- 09.2021 05.2026
- Without a fix
- 1
- Exploited in attacks
- 0
Severity breakdown
- High 1
- Medium 1
Disclosures per year
- 2021: 1
- 2022: 0
- 2023: 0
- 2024: 0
- 2025: 0
- 2026: 1
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