Vulnerability record/PUBLISHED/Published Nov 11, 2026 00:58:50 UTC

CVE-2026-126498

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.

Base score5.1/ 10

SeverityMediumCVSS 4.0

Exploitability / impact

CVSS metric breakdown

Vector-derived attributes

Base severityMedium

Attack vectorNetworkAV

Attack complexityLowAC

Attack requirementsNoneAT

Privileges requiredLowPR

User interactionPassiveUI

Vulnerable system confidentialityLowVC

Vulnerable system integrityLowVI

Vulnerable system availabilityNoneVA

Subsequent system confidentialityLowSC

Subsequent system integrityLowSI

Subsequent system availabilityNoneSA

CVSS vector stringCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N

CVSS communicates standardized severity and impact characteristics. It does not establish whether a system is exploitable in your specific environment.

Record context

CVE Numbering AuthorityVulnCheck

Last updatedNov 14, 2026 03:11:37 UTC

PublishedNov 11, 2026 00:58:50 UTC

ReservedNov 10, 2026 21:45:21 UTC

Credits

George Chen