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CVE-2026-30789 rustdesk-client CVE debrief

CVE-2026-30789 is a critical vulnerability in RustDesk Client affecting Windows, MacOS, Linux, iOS, and Android platforms. It allows for Authentication Bypass by Capture-replay and Use of Password Hash With Insufficient Computational Effort, specifically through reusing session IDs (Session Replay). This issue impacts client login and peer authentication modules, associated with program files src/client.Rs and routines hash_password(), login proof construction. Affected versions are up to 1.4.5. Defenders should prioritize patching due to the high CVSS score of 9.3.

Vendor
rustdesk-client
Product
Unknown
CVSS
MEDIUM 5.7
CISA KEV
Not listed in stored evidence
Original CVE published
2026-03-05
Original CVE updated
2026-06-22
Advisory published
2026-03-05
Advisory updated
2026-06-22

Who should care

Organizations and individuals using RustDesk Client versions up to 1.4.5 on Windows, MacOS, Linux, iOS, and Android should prioritize patching. This vulnerability allows for session replay attacks, posing a significant risk to authentication security.

Technical summary

The vulnerability, CVE-2026-30789, is caused by insufficient computational effort in password hashing and the reuse of session IDs, enabling session replay attacks. It affects RustDesk Client's client login and peer authentication modules. The CVSS vector is CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X.

Defensive priority

High priority due to critical CVSS score of 9.3 and potential for session replay attacks.

Recommended defensive actions

  • Apply patches or updates to RustDesk Client to version beyond 1.4.5.
  • Review and update authentication configurations to ensure secure session management.
  • Implement additional monitoring for unusual authentication attempts.
  • Consider compensating controls such as multi-factor authentication.
  • Inventory and track RustDesk Client installations for compliance.

Evidence notes

The CVE record and NVD detail provide evidence of the vulnerability's existence and impact. The CVSS score of 9.3 indicates critical severity. Affected products include RustDesk Client up to version 1.4.5 on multiple platforms. Verify platform and version information with official sources.

Sources and references

Verified primary and authoritative sources

  • CVE-2026-30789 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2026-30789

    CVE Program - Official CVE Program record with source-provided CVE metadata.

  • CVE-2026-30789 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2026-30789

    NIST National Vulnerability Database - Official NIST NVD detail page and source-specific vulnerability assessment.

Supplemental references

  • Mitigation or vendor reference

    Unverified legacy reference

    URL: https://docs.google.com/document/d/e/2PACX-1vSds6jjpd38oO_yIAyd1HYtKNUuea-I-ozAPpGhYI7QgAU-QGJ7D8a4rOZVj1vmiUXV1EcdRHf9aZAW/pub

    2fdefc65-d750-4b8d-96ee-6e2c0c42dbfe - Exploit, Third Party Advisory

  • Source reference

    Unverified legacy reference

    URL: https://rustdesk.com/docs/en/client/

    2fdefc65-d750-4b8d-96ee-6e2c0c42dbfe - Product

  • Source reference

    Unverified legacy reference

    URL: https://www.vulsec.org/

    2fdefc65-d750-4b8d-96ee-6e2c0c42dbfe - Not Applicable

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.