In admin/write-post.php in Typecho through 1.1, one can log in to the background page, write a new article, and add payload in the article content, resulting in XSS via index.php/action/contents-post-edit.
Severity
CVSS 3.0
5.4 medium
CVSS:3.0/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
EPSS
0.5% chance of exploitation in the next 30 days; higher than 43% of CVEs (scores of 2026-10-31)