CVE-2026-126498
WriteFreely before 0.17.3 Stored XSS via Unsanitized Post Slug
CVSS Score
5.4
EPSS Score
0.0%
EPSS Percentile
0th
WriteFreely before 0.17.3 contains a stored cross-site scripting vulnerability that allows authenticated authors to inject HTML by supplying a malicious post slug via the CreatePost API. The raw slug is concatenated into an anchor by augmentReadingDestination() for paid-shortcode posts, executing script for RSS/Atom feed readers, newsletter recipients and ActivityPub viewers.
| CWE | CWE-79 |
| Vendor | musing studio |
| Product | writefreely |
| Published | Nov 11, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N Attack Vector
Network
Attack Complexity
Low
Privileges Required
Low
User Interaction
Required
Scope
Changed
Confidentiality
Low
Integrity
Low
Availability
None
Affected Versions
Musing Studio / WriteFreely
0 < 0.17.3
References
github.com: https://github.com/writefreely/writefreely/security/advisories/GHSA-cwxm-8ch5-j2vh github.com: https://github.com/writefreely/writefreely/commit/d7231d81a914f1314a218d5e8fde6e0341391ccd github.com: https://github.com/writefreely/writefreely/releases/tag/v0.17.3 github.com: https://github.com/writefreely/writefreely/blob/v0.17.2/postrender.go#L117-L121 github.com: https://github.com/writefreely/writefreely/blob/v0.17.2/database.go#L702-L705 vulncheck.com: https://www.vulncheck.com/advisories/writefreely-before-0.17.3-stored-xss-via-unsanitized-post-slug
Credits
George Chen