CVE-2026-56843
criticalpriority · track · 0EPSS 0.007 · 51 %ileEUEPSS · scored 2026-10-27
Incorrect authorization in the XML-RPC API of WebPros Plesk before 18.0.78.4 allows a low-privileged authenticated customer to look up domains they do not own, because ownership is enforced only for certain lookup filters and schema validation is bypassed for legacy protocol versions. This results in cross-tenant disclosure of other tenants' FTP credentials stored in cleartext, which can be leveraged to execute code as another tenant's system user.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (1)
Products and version ranges known to be affected.
also known as (3)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (4)
External citations — patches, advisories, analysis.
- https://support.plesk.com/hc/en-us/articles/41178305151255-Vulnerability-CVE-2026-56843-Cleartext-FTP-Password-Exposure-in-Plesk-s-XML-APIPatchcnnvd
- https://support.plesk.com/hc/en-us/articles/41178305151255-Vulnerability-in-Plesk-XML-API-Cleartext-FTP-Password-Exposurecnnvd
- https://support.plesk.com/hc/en-us/articles/41178305151255-Vulnerability-in-Plesk-XML-API-Cleartext-FTP-Password-Exposureenisa_euvd
- https://support.plesk.com/hc/en-us/articles/41178305151255-Vulnerability-in-Plesk-XML-API-Cleartext-FTP-Password-Exposurenvd
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