CVE-2026-66703: MailOptin (WordPress plugin) · Cross-site Scripting
Affects MailOptin (WordPress plugin)Source CVE Database V5
Not known to be exploited · CVSS 6.5 Medium.
Data as of 5 Nov 2026, 00:01 UTC
- EPSS
- 0.2% chance of exploitation in 30 days – higher than 13% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:LExploitation evidence
Disclosed: evidence found.
CVE published 6 Aug 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 5 Nov 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| properfractionMailOptin | Affected
| Fixed in– |
AI-suggested
Until an official fix is available, consider restricting privileges and limiting user interactions that could trigger the vulnerability. Monitor vendor channels for updates.
Description
CVE-2026-66703 is a cross-site scripting (XSS) vulnerability in the properfraction MailOptin plugin affecting versions up to and including 1.2.78.0. This vulnerability allows improper neutralization of input during web page generation, potentially leading to limited confidentiality, integrity, and availability impacts. The vulnerability requires low attack complexity but some privileges and user interaction. No official patch or remediation guidance is currently available.