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CVE-2026-30790 rustdesk-client CVE debrief

CVE-2026-30790 is a critical vulnerability in RustDesk Client that allows for interception and offline password brute forcing due to the use of a password hash with insufficient computational effort. The vulnerability affects RustDesk Client versions through 1.4.8 and is associated with program files src/client.rs and src/common.rs. The controlled-host peer authentication channel is not affected, but the Server Pro /api login path is vulnerable due to the use of TLS alone and an automatic invalid-certificate downgrade. Defenders should prioritize patching and review their current configurations to limit exposure.

Vendor
rustdesk-client
Product
Unknown
CVSS
HIGH 8.2
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

Defenders who use RustDesk Client, especially those using Server Pro, should prioritize patching and review their current configurations to limit exposure. This vulnerability has a CVSS score of 9.3 and is considered critical.

Technical summary

The vulnerability is caused by the use of a fast double SHA256 over a server-controlled salt and challenge with no slow KDF, making it vulnerable to offline password brute forcing. The controlled-host peer authentication channel is not affected due to the use of XSalsa20-Poly1305 secretbox session. However, the Server Pro /api login path is vulnerable due to the use of TLS alone and an automatic invalid-certificate downgrade.

Defensive priority

High priority due to critical CVSS score and potential for interception and offline password brute forcing.

Recommended defensive actions

  • Apply patches to RustDesk Client versions through 1.4.8
  • Review and update Server Pro configurations to use secure authentication channels
  • Implement additional security measures such as multi-factor authentication
  • Monitor for suspicious activity and implement incident response plans
  • Review and update incident response plans to address potential exploitation

Evidence notes

The primary evidence for this vulnerability is the CVE record and the NVD detail page. The vulnerability affects RustDesk Client versions through 1.4.8. Defenders should verify the affected products and versions from official sources.

Sources and references

Verified primary and authoritative sources

  • CVE-2026-30790 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2026-30790

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

  • CVE-2026-30790 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2026-30790

    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://github.com/rustdesk

    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.