Medium severity · published Sep 17, 2026
CVE-2026-91011
EWWW Image Optimizer < 8.7.7 - Author+ Stored XSS via Image Class Attribute Backreference Expansion
6.8
CVSS
0.4%
EPSS
No
On KEV
Description
The EWWW Image Optimizer WordPress plugin before 8.7.7 does not properly escape image attribute values when it rewrites page output, allowing authenticated users with author-level access and above to inject arbitrary JavaScript that is stored in published content and executes in the browser of any user who later views the affected page.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
High
User interaction
Required
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 37% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
EI
EWWW Image Optimizer ·
before 8.7.7 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-91011
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-91011
wpscan.com
https://wpscan.com/vulnerability/334f14d5-f97b-4ec5-9b42-bb0803ae1668/
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