10 November 2026

KLCERT-26-059: TrueConf Server (Linux). Incorrect Default Permissions

Vendor

TrueConf

Researchers

Grigory SablinDigital Forensic and Incident Response Group Manager

Vyacheslav KopeytsevPrincipal Security Researcher

Timeline

Timeline

  • Kaspersky ICS CERT advisory published

    10 November 2026

  • Vendor Informing

    August 2026

Description

An attacker who gains the ability to execute arbitrary code on a system with TrueConf Server (Linux) versions up to 5.5.6 installed, running as the user trueconf (by exploiting some other vulnerability), can elevate their privileges to root.


Exploitability

Local

Attack complexity

Low

Privilege required

Low: the ability to execute arbitrary code as user 'trueconf' is required

User interaction

None

Confidentiality

High

Integrity

High

Availability

High

Impact

Exploitation of this vulnerability could allow a local attacker to escalate privileges to root.

Affected products

TrueConf Server (Linux):

  • All versions from 4.7.2 up to, but not including, 5.5.6

Mitigation

Kaspersky ICS CERT mitigation

  • Update TrueConf Server (Linux) to version 5.5.6 or newer.
  • Perform a full check with antivirus software that has up-to-date antivirus databases and modules.

Timeline

  • Kaspersky ICS CERT advisory published

    10 November 2026

  • Vendor Informing

    August 2026