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PatchSiren cyber security CVE debrief

CVE-2026-30794 rustdesk-client CVE debrief

CVE-2026-30794 is a CRITICAL Improper Certificate Validation vulnerability in RustDesk Client on Windows, MacOS, Linux, iOS, Android. The vulnerability allows for Adversary in the Middle (AiTM) attacks. It affects RustDesk Client through version 1.4.8, specifically in the HTTP API client and TLS transport modules. The CVSS score is 9.1, indicating a high severity. Defenders should prioritize patching due to the potential for significant impact and the critical severity of this vulnerability.

Vendor
rustdesk-client
Product
Unknown
CVSS
CRITICAL 9.1
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 using RustDesk Client, especially those in environments where secure communication is paramount, should prioritize patching this vulnerability. This includes but is not limited to remote work setups, organizations with sensitive data, and those in industries with strict security compliance requirements.

Technical summary

The vulnerability is caused by improper certificate validation in the RustDesk Client, specifically in the src/hbbs_http/http_client.Rs file and the TLS retry mechanism with danger_accept_invalid_certs(true). This allows attackers to intercept and manipulate communications, potentially leading to unauthorized access or data breaches. The vulnerability affects RustDesk Client versions through 1.4.8 on multiple platforms including Windows, MacOS, Linux, iOS, and Android.

Defensive priority

High priority due to CRITICAL CVSS score of 9.1 and potential for AiTM attacks.

Recommended defensive actions

  • Inventory and update RustDesk Client to a version beyond 1.4.8.
  • Review and enforce secure certificate validation practices for TLS communications.
  • Implement compensating controls such as network monitoring for suspicious activity.
  • Limit exposure by restricting access to sensitive data and systems.
  • Monitor for and apply any additional security patches or advisories from the vendor.

Evidence notes

The primary evidence for this vulnerability comes from the CVE record and NVD detail pages. The vulnerability affects RustDesk Client through version 1.4.8. Defenders should verify the version of RustDesk Client in use and check for any official advisories or patches from the vendor. The CVE and NVD entries provide critical details about the vulnerability's impact and affected configurations.

Sources and references

Verified primary and authoritative sources

  • CVE-2026-30794 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2026-30794

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

  • CVE-2026-30794 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2026-30794

    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/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.