An attacker who gains the ability to execute arbitrary code on a system with TrueConf Server (Linux) versions from 4.7.2 up to, but not inc…

published 2026-11-11 20h ago modified 2026-11-12 5h ago also EUVD-2026-123528

cvss: 7.8; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: —; no EPSS score yet
public exploits: 0; none known

An attacker who gains the ability to execute arbitrary code on a system with TrueConf Server (Linux) versions from 4.7.2 up to, but not including, 5.5.6 installed, running as the user trueconf (by exploiting some other vulnerability), can elevate their privileges to root.

Patch / fix

fixed in 1

TrueConf TrueConf Server 5.5.6

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CISA SSVC

Exploitation: none
Automatable: no
Technical impact: total
Assessed: yesterday (2026-11-11)

CVSS scores

assigned by	version	score	vector
CNA	4.0	8.5	CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
CNA	3.1	7.8	CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CNA	4.0	8.5	CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/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

Affected products

TrueConf TrueConf Server

Classification

Weakness

CWE-276 Incorrect Default Permissions

References

ics-cert.kaspersky.com /advisories/2026/11/10/trueconf-server-linux-incorrect-default-permissions/
third-party-advisory

Sources

CVE List CVE-2026-123040
NVD CVE-2026-123040

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