CVE-2026-44742 Postorius is vulnerable to XSS
Attackers can execute arbitrary scripts in the Postorius held messages pop-up due to unescaped HTML in message subjects, potentially compromising user accounts.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-44742?
CVE-2026-44742 is a high-severity cross-site scripting vulnerability in Postorius, published on 7 May 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official 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.
Weakness: CWE-79
Which versions are affected by CVE-2026-44742?
3 open source packages ship an affected version, including postorius. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
postorius PyPI | All versions to 1.3.13 | None |
postorius PyPI | All versions to 1.3.13 | None |
postorius PyPI | All versions to 1.3.13 | None |
Linux distribution packages (1)
python-postorius openSUSE:Tumbleweed | All versions | 1.3.13-8.1 |
Products include Postorius Project Postorius.
How do I fix CVE-2026-44742?
Upgrade to a fixed version.
Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.
Is CVE-2026-44742 being exploited?
There is no known exploitation of CVE-2026-44742 in the wild and no public exploit code.
Other vulnerabilities in Postorius
Sources
Also known as DEBIAN-CVE-2026-44742, GHSA-r7c9-7pjq-hmm8, PYSEC-2026-2891, UBUNTU-CVE-2026-44742, USN-8323-1, openSUSE-SU-2026:11539-1.