Beckhoff TwinCAT 2.11.0.2004 and earlier allows remote attackers to cause a denial of service via a crafted request to UDP port 48899, whic…

published 2011-09-16 15 y ago modified 2026-06-16 4 mo ago also EUVD-2011-3449

cvss: 5.0; version 2.0, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 49.6%; EPSS 49.6% chance of exploitation in 30 days, percentile 98%
public exploits: 2; Metasploit, Exploit-DB

Beckhoff TwinCAT 2.11.0.2004 and earlier allows remote attackers to cause a denial of service via a crafted request to UDP port 48899, which triggers an out-of-bounds read.

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

cisa ICSA-11-279-04 updated 2025-06-09 cvss 5.0

Beckhoff TwinCAT Read Access Violation

Beckhoff TwinCAT 2.10, 2.11, 2.11R2
affected: mitigation “Beckhoff has developed a patch to address this vulnerability. To obtain the patch and installation instructions, customers should contact Beckhoff at (mailto:patch@beckhoff.com).”

From CISA ICS and IT advisories (CSAF, https://github.com/cisagov/CSAF), a U.S. Government work; changed: reduced to products, statuses and remediations. CISA notification · csaf

Timeline

2011-09-13 First public exploit (Metasploit auxiliary/dos/scada/beckhoff_twincat)
2011-09-16 Published

Exploit prediction

49.65% chance of exploitation in the next 30 days, higher than 98% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

Metasploit auxiliary/dos/scada/beckhoff_twincat Beckhoff TwinCAT SCADA PLC 2.11.0.2004 DoS metasploit auxiliary, normal rank, 2011-09-13
EDB-17835 Beckhoff TwinCAT 2.11.0.2004 - Denial of Service dos, 2011-09-14
aluigi.altervista.org http://aluigi.altervista.org/adv/twincat_1-adv.txt referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
NVD	2.0	5.0	AV:N/AC:L/Au:N/C:N/I:N/A:P

Classification

Weakness

CWE-119 Improper Restriction of Operations within the Bounds of a Memory Buffer

References

aluigi.altervista.org /adv/twincat_1-adv.txt
exploit
exchange.xforce.ibmcloud.com /vulnerabilities/69765
vdb-entry
securityreason.com /securityalert/8380
third-party-advisory
us-cert.gov /control_systems/pdf/ICS-ALERT-11-256-06.pdf
us-government-resource
osvdb.org /75495
vdb-entry

Sources

CVE List CVE-2011-3486
NVD CVE-2011-3486

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary