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TI-2026-40985 Aliases CVE-2026-56843GHSA-m4rp-7vj2-ggpc

Insufficiently protected credentials in WebPros Plesk

Priority MEDIUM 44CWE-522Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Information disclosure
Confidentiality · integrity · availability
High · High · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-522.

Summary

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00655 51st percentileScored 2026-11-07
Fix Fixed Plesk (Webpros): 18.0.78.4

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
WebProsPlesk10.4 to before 18.0.78.418.0.78.4Patch availableCNA
  • Plesk VendorWebPros Affected 10.4 to before 18.0.78.4 Fixed in 18.0.78.4 Patch available CNA

Remediation

  • Fix · CNA Plesk (Webpros) Fixed in 18.0.78.4

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-56843
  2. 2026-10-03 Alias added: GHSA-m4rp-7vj2-ggpc
  3. 2026-10-13 EPSS moved to the 50th–90th percentile

References

Other 1

  • TI-2026-30342 WebPros cPanel and WHM Authentication Bypass via Login Flow KEVCVSS 4.0CRITICAL 9.3
  • TI-2026-46792 Eval injection in cPanel 11.138.0.0 and earlier allows remote authenticated users to execute arbitrary code as root. CVSS 4.0HIGH 8.7
  • TI-2025-40383 Plesk Obsidian versions 8.0.1 through 18.0.73 are vulnerable to a Denial of Service (DoS)… CVSS 3.1HIGH 7.5
  • TI-2026-23322 Incorrect privileges management and insufficient path filtering allow to read arbitrary… CVSS 3.1HIGH 8.6
  • TI-2026-47685 Deserialization of untrusted data in WebPros WHMCS CVSS 4.0CRITICAL 9.3
  • TI-2026-23317 Authorization bypass in WebPros Comet Backup CVSS 4.0CRITICAL 9.9
See all 50 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences