CVE-2026-72529: TrueConf Server Missing Authentication for Critical Function Vulnerability

Patch now

CRITICAL 9.8EXPLOITEDREMOTEUPGRADEUPGRADE

CVE-2026-72529 is a critical-severity flaw (CVSS 9.8) affecting trueconf server, trueconf server, reported as exploited in the wild. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

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 execute an arbitrary script by calling an undocumented function.

Why this priority

Critical severity
Exploited in the wild (CISA KEV)
Public exploit reference
CISA SSVC: automatable with total technical impact
Remotely exploitable, no login, no user action

A fixed release or distro patch exists.

Risk facts

CVSS score	9.8 (Critical)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	None
EPSS exploit chance	1.5% (top 27%)
CISA exploited list	Yes, fix due 2026-08-23
Weakness	CWE-306
Published	2026-08-19
Last modified	2026-08-21

Publisher (CNA): Kaspersky Labs · Vendor: trueconf

Last updated 2026-08-21 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2026-08-19 17:21 UTCPublished CVE record published
2026-08-20Exploited Added to the CISA Known Exploited Vulnerabilities list
2026-08-21 04:18 UTCUpdated Record last modified
2026-08-23Deadline CISA due date for US federal agencies to patch

trueconf trueconf server UPGRADE

Affected: < 5.3.9.10013 · >= 5.4.0.12689 and < 5.4.9.10072 · >= 5.5.0.13826 and < 5.5.5.10010

Fixed in: 5.3.9.10013, 5.4.9.10072, 5.5.5.10010

Safe to downgrade to: a release before 5.4.0.12689

1. Check installed version

apt-cache policy trueconf-server || rpm -q trueconf-server || trueconf-server --version

2. UPGRADE to 5.3.9.10013 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade trueconf-server

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade trueconf-server

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

3. If no update is available yet, DOWNGRADE to a release before 5.4.0.12689 (Debian / Ubuntu)

apt-cache madison trueconf-server sudo apt install trueconf-server=<VERSION_BEFORE_5.4.0.12689> sudo apt-mark hold trueconf-server

3. If no update is available yet, DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list trueconf-server sudo dnf downgrade trueconf-server-<VERSION_BEFORE_5.4.0.12689> sudo dnf versionlock add trueconf-server

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

trueconf trueconf server UPGRADE

Affected: < 5.3.9.10015 · >= 5.4.0.12700 and < 5.4.9.10019 · >= 5.5.0.13828 and < 5.5.5.10009

Fixed in: 5.3.9.10015, 5.4.9.10019, 5.5.5.10009

Safe to downgrade to: a release before 5.4.0.12700

1. Check installed version

apt-cache policy trueconf-server || rpm -q trueconf-server || trueconf-server --version

2. UPGRADE to 5.3.9.10015 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade trueconf-server

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade trueconf-server

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

3. If no update is available yet, DOWNGRADE to a release before 5.4.0.12700 (Debian / Ubuntu)

apt-cache madison trueconf-server sudo apt install trueconf-server=<VERSION_BEFORE_5.4.0.12700> sudo apt-mark hold trueconf-server

3. If no update is available yet, DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list trueconf-server sudo dnf downgrade trueconf-server-<VERSION_BEFORE_5.4.0.12700> sudo dnf versionlock add trueconf-server

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

Verify at the official source NVD · CVE Program · CISA KEV catalog · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2026-72529?

trueconf server: upgrade to 5.3.9.10013, 5.4.9.10072, 5.5.5.10010; trueconf server: upgrade to 5.3.9.10015, 5.4.9.10019, 5.5.5.10009. Exact commands for each OS are on this page.

Is CVE-2026-72529 being exploited?

Yes. CVE-2026-72529 is on the CISA Known Exploited Vulnerabilities list, so treat it as patch-now.

What does CVE-2026-72529 affect?

CVE-2026-72529 affects trueconf server, trueconf server. Severity is critical (CVSS 9.8). 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 execute an arbitrary script by calling an undocumented function.

How urgent is CVE-2026-72529?

Priority 91/100. Critical severity; Exploited in the wild (CISA KEV); Public exploit reference; CISA SSVC: automatable with total technical impact; Remotely exploitable, no login, no user action

Related CVEs

CVE-2026-72530 CRITICAL 9.0 EXPLOITED UPGRADE UPGRADE TrueConf Server Code Injection Vulnerability

References

← Back to latest CVEs