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.
Affected products
postorius_project: postorius
References5
- gitlab.com/mailman/postorius/-/issues/620 Issue TrackingVendor Advisory
- gitlab.com/mailman/postorius/-/commit/c4706abd05ba6bcf472fc674b… Patch
- gitlab.com/mailman/postorius/-/merge_requests/972 Issue TrackingPatch
- www.openwall.com/lists/oss-security/2026/05/07/3 Mailing ListPatchThird Party Advisory
- lists.debian.org/debian-lts-announce/2026/05/msg00045.html
Metrics
- CVSS 3.1
-
6.1
MEDIUM
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N - EPSS — exploit probability
- 0% percentile: 15 · as of 13 November 2026
- CWE
- CWE-79
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