Low severity · published Oct 19, 2026
CVE-2026-91831
Subscribe to Comments 2.3 - 2.3.2 - Author+ Email Header Injection via From Name Setting
3.8
CVSS
0.2%
EPSS
No
On KEV
Description
The Subscribe to Comments WordPress plugin before 2.3.3 does not sanitise newline characters from a notification sender-name setting before using it in e-mail headers, allowing users with Author-level access and above to inject arbitrary e-mail headers, such as a hidden Bcc, and to spoof the sender.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
High
User interaction
None
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 5% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
ST
Subscribe to Comments ·
2.3 before 2.3.3 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-91831
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-91831
wpscan.com
https://wpscan.com/vulnerability/6cd60f78-f5e2-4b4a-8d50-7d2bc4f981ee/
More from Subscribe to Comments
7.1
CVE-2026-91829
Subscribe to Comments < 2.3.3 - Reflected XSS via 'ref' Parameter
6.5
CVE-2026-91830
Subscribe to Comments < 2.3.3 - Unauthenticated Subscription Management Key Disclosure via Forged Comment Cookie