CVE-2026-72530
CVE-2026-72530 is a security flaw in TrueConf Server. Attackers can run their own code on TrueConf Server. The US Cybersecurity and Infrastructure Security Agency (CISA) added it to its catalog of flaws known to be used in attacks on 20 Aug 2026.[1]
TrueConf Server is business software or equipment. Most families won’t have it, but attackers break into it to get inside companies, and from there to what those companies hold about their customers, patients and staff. Fixed in version 5.3, 5.3.9, 5.4.9 and 5.5.5 of TrueConf Server.
Description
CISA calls it a code injection in TrueConf Server. In its words: “TrueConf Server contains a code injection vulnerability that could allow an unauthorized remote attacker with network access via port 4307/TCP to use a specially crafted script to break out of the isolated environment and execute arbitrary code on the host system.”[1]
The underlying weakness is code injection (CWE-94), in MITRE’s list of common software weaknesses.[2]
It scores 9.0 out of 10 on the Common Vulnerability Scoring System, which rates it critical, scored by the organisation that published the CVE using CVSS 3.1.[2]
Affected versions
NVD’s record lists these fixed versions: in each line, everything before the version shown is affected.[2]
| Product | Fixed in |
|---|---|
| TrueConf Server | 5.3 |
| TrueConf Server | 5.3.9 |
| TrueConf Server | 5.4.9 |
| TrueConf Server | 5.5.5 |
Most families won’t have TrueConf Server; it’s for whoever looks after IT at work.
Exploitation
CISA added it to its catalog of known exploited vulnerabilities on 20 Aug 2026, within a day of it being made public. CISA lists a flaw only when it has reliable evidence of it being exploited, and gave US federal agencies until 3 Sep 2026 to fix it.[1]
FIRST’s Exploit Prediction Scoring System, which estimates how likely a flaw is to be used in attacks in the next 30 days from what it sees across the internet, puts it at 2%. That’s in the top 23% of the flaws it scores.[4]
CISA assesses it as not automatable: each attack takes some work.
CISA doesn’t say who was attacked, or how.
Fix
TrueConf has published a fix or advice.[3] CISA’s required action: “Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes).”[1]
- Check whether you use it.TrueConf Server is business software or equipment, so most families won’t have it. If you run a business, or work from home on company equipment, ask whoever looks after your IT.
- Send this page to your IT person.Ask them to confirm it’s fixed (fixed in version 5.3, 5.3.9, 5.4.9 and 5.5.5 of TrueConf Server), or not in use. CISA gave US government agencies until 3 Sep 2026 to fix it.
- If it can’t be fixed, take it offline.CISA’s advice when there’s no fix is to stop using the product, or take it off the internet, until there is one.
You can’t fix someone else’s server, but you can watch for what follows a break-in like this: a breach notice, a password reset you didn’t ask for, or a scam message that knows things it shouldn’t. HARD watches for those for you and your family.
Timeline
| Date | Event |
|---|---|
| The flaw is made public in the National Vulnerability Database, with a severity score of 9.0.[2] | |
| CISA adds it to its catalog of flaws known to be used in attacks.[1] | |
| CISA’s deadline for US government agencies to fix it.[1] | |
| FIRST puts the odds of it being used in attacks in the next 30 days at 2%.[4] |
See also
Other TrueConf Server flaws
- CVE-2026-72529: missing authentication for critical function ·
Other TrueConf flaws
- CVE-2026-3502, TrueConf Client: download of code without integrity check ·
Other code injection flaws
- CVE-2026-0322, Palo Alto Networks PAN-OS: code injection ·
- CVE-2026-65660, Microsoft SharePoint: code injection ·
- CVE-2026-60004, Gitea: code injection ·
- CVE-2025-62593, Ray-Project Ray: code injection ·
- CVE-2026-9198, IBM Langflow: code injection ·
Added the same day
- CVE-2026-72529, TrueConf Server: missing authentication for critical function ·
Every TrueConf flaw on CISA’s list · Everything added in August 2026
References
- ^ Cybersecurity and Infrastructure Security Agency. “TrueConf Server Code Injection Vulnerability”. Known Exploited Vulnerabilities Catalog, added 20 Aug 2026.
- ^ National Institute of Standards and Technology. “CVE-2026-72530 Detail”. National Vulnerability Database, published 19 Aug 2026.
- ^ TrueConf. Advisories and fixes: trueconf.com, ics-cert.kaspersky.com.
- ^ FIRST. “Exploit Prediction Scoring System”. EPSS 0.017, percentile 77.0, 31 Oct 2026.
- CVE Program. “CVE-2026-72530”. The official CVE record.
This article is built from CISA’s catalog (version 2026.10.30), NVD’s record and FIRST’s scores, kept in HARD’s database and checked every morning. The plain English is HARD’s.