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CVE-2026-72530: TrueConf Server Code Injection Vulnerability

CVE-2026-72530 is rated critical with a CVSS v3.1 base score of 9.0 and affects TrueConf Server. Per its scoring, it can be exploited over the network, without authentication, without any user interaction. The scored impact on confidentiality, integrity and availability is the highest available. CISA added it to its Known Exploited Vulnerabilities catalog on 2026-08-20, which means exploitation in the wild has been observed.

Vulnerability description

A remote unauthorized attacker with network access via port 4307/TCP to the TrueConf server versions 5.3.X to 5.3.9, 5.4.X to 5.4.9, 5.5.X to 5.5.5, and earlier could use a specially crafted script to break out of the isolated environment and execute arbitrary code on the host system.

Severity breakdown

CVSS v3.1 9.0: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H

  • Attack vector: Network. Exploitable remotely over the network, with no need for local or physical access.
  • Attack complexity: High. Success depends on conditions outside the attacker’s control.
  • Privileges required: None. No account or prior access is needed.
  • User interaction: None. No action from any user is needed.
  • Scope: Changed. Impact reaches beyond the vulnerable component to other resources.
  • Confidentiality impact: High. Total loss of confidentiality; sensitive data can be fully disclosed.
  • Integrity impact: High. Total loss of integrity; data or system state can be fully modified.
  • Availability impact: High. Total loss of availability; the component can be shut down.

Underlying weakness

CWE-94: Improper Control of Generation of Code

The product constructs all or part of a code segment using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the syntax or behavior of the intended code segment.

Affected products

  • Trueconf Server: before 5.3.9.10013; before 5.3.9.10015; from 5.4.0.12689 before 5.4.9.10072; from 5.4.0.12700 before 5.4.9.10019; from 5.5.0.13826 before 5.5.5.10010; from 5.5.0.13828 before 5.5.5.10009

References