Medium severity · published Oct 2, 2026
CVE-2026-104446
YesWiki before 4.6.7 Unauthenticated Open Mail Relay via Contact Mail Handler
6.5
CVSS
0.4%
EPSS
No
On KEV
Description
YesWiki before 4.6.7 contains an authentication bypass in the contact mail AJAX handler that allows unauthenticated attackers to send email through the wiki's SMTP server. Attackers can POST an XMLHttpRequest to the mail handler without field or type parameters, supplying arbitrary recipient, sender, subject and body for spam and phishing.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
Low
Availability
Low
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 38% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
YE
yeswiki · YesWiki
before 4.6.7 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-104446
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-104446
vendor-advisory
https://github.com/YesWiki/yeswiki/security/advisories/GHSA-36fx-49jj-57rw
third-party-advisory
https://www.vulncheck.com/advisories/yeswiki-before-4.6.7-unauthenticated-open-mail-relay-via-contact-mail-handler
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