# What is CVE-2019-10939? > CVE-2019-10939 is a critical-severity flaw (CVSS 9.8) in Tim 3v-Ie from Siemens, published on 14 April 2020. It is not on the list of flaws known to be exploited today. The latest forecast puts its chance of use in the next 30 days at 1.1%. If you run an affected version, plan in the vendor’s fix. Canonical page: https://www.precursorintelligence.com/what-is/cve-2019-10939 ## At a glance - **Verdict:** Fix this soon. Not confirmed as exploited yet, but serious or likely enough that it should not wait for a quiet month. - **Precursor Intelligence risk score:** 54 out of 100 (Medium); action: Plan remediation. Kept up to date as the evidence changes. - **Severity:** Critical (CVSS 9.8 out of 10) - **Known to be exploited:** No, not on the list of flaws known to be exploited today - **Chance of use in the next 30 days:** 1.1% (latest exploit-likelihood forecast) - **Published:** 14 April 2020 - **Record last updated:** 5 October 2020 - **Main product:** Tim 3v-Ie from Siemens - **Affected products:** 10 ## What is CVE-2019-10939? In plain terms It can be attacked from anywhere on the internet without logging in, and nobody has to click anything. If it works, the attacker can read data, change data and take it offline. ### The official description A vulnerability has been identified in TIM 3V-IE (incl. SIPLUS NET variants) (All versions < V2.8), TIM 3V-IE Advanced (incl. SIPLUS NET variants) (All versions < V2.8), TIM 3V-IE DNP3 (incl. SIPLUS NET variants) (All versions < V3.3), TIM 4R-IE (incl. SIPLUS NET variants) (All versions < V2.8), TIM 4R-IE DNP3 (incl. SIPLUS NET variants) (All versions < V3.3). The affected versions contain an open debug port that is available under certain specific conditions. The vulnerability is only available if the IP address is configured to 192.168.1.2. If available, the debug port could be exploited by an attacker with network access to the device. No user interaction is required to exploit this vulnerability. The vulnerability impacts confidentiality, integrity, and availability of the affected device. At the stage of publishing this security advisory no public exploitation is known. ### What kind of flaw is it? - CWE-489: Active Debug Code ### How an attack on it works - Where an attacker can be: Anywhere on the internet - How hard it is to pull off: Easy: no special conditions - Login needed first: No login needed - Does someone have to click: No, nobody has to do anything - What an attacker gets: Can read data, change data and take it offline Severity vector: `CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H` ## Is CVE-2019-10939 being exploited? Not that we know of It is not on the list of flaws known to be exploited today. The latest forecast puts the chance of it being used in the next 30 days at 1.1%. That can change at any time, which is why we keep watching. Exploit likelihood over the last 7 days: 1.1%, 1.1%, 1.1%, 1.1%, 1.1%, 1.1%, 1.1%. ### Timeline - 14 April 2020: Published - 5 October 2020: Record last updated ### How Precursor Intelligence ranks it CVE-2019-10939 scores **54 out of 100 (Medium)**, with the action "Plan remediation". Every published flaw gets a risk score from 0 to 100, kept up to date as the evidence changes. Four things go into the score, from the one that counts most to the ones that count less: - Evidence it is being exploited: biggest factor - How severe it is: strong factor - How widely exposed it is: smaller factor - Threat activity around it: smaller factor 85 and above is Critical. Anything confirmed as exploited is always marked for an emergency patch, whatever its score. When this flaw matches software you track, it lands in your list with its score and the reasons behind it. ## Who is affected by CVE-2019-10939? The published record lists 10 products. Versions are as published: "before 2.8" means every version up to, but not including, 2.8. - [Tim 3v-Ie](https://www.precursorintelligence.com/product/siemens/tim_3v-ie) by [Siemens](https://www.precursorintelligence.com/vendors/siemens) (Hardware): version not specified - [Tim 3v-Ie Advanced](https://www.precursorintelligence.com/product/siemens/tim_3v-ie_advanced) by [Siemens](https://www.precursorintelligence.com/vendors/siemens) (Hardware): version not specified - [Tim 3v-Ie Advanced Firmware](https://www.precursorintelligence.com/product/siemens/tim_3v-ie_advanced_firmware) by [Siemens](https://www.precursorintelligence.com/vendors/siemens) (Operating system): before 2.8 - [Tim 3v-Ie Dnp3](https://www.precursorintelligence.com/product/siemens/tim_3v-ie_dnp3) by [Siemens](https://www.precursorintelligence.com/vendors/siemens) (Hardware): version not specified - [Tim 3v-Ie Dnp3 Firmware](https://www.precursorintelligence.com/product/siemens/tim_3v-ie_dnp3_firmware) by [Siemens](https://www.precursorintelligence.com/vendors/siemens) (Operating system): before 2.8 - [Tim 3v-Ie Firmware](https://www.precursorintelligence.com/product/siemens/tim_3v-ie_firmware) by [Siemens](https://www.precursorintelligence.com/vendors/siemens) (Operating system): before 2.8 - [Tim 4r-Ie](https://www.precursorintelligence.com/product/siemens/tim_4r-ie) by [Siemens](https://www.precursorintelligence.com/vendors/siemens) (Hardware): version not specified - [Tim 4r-Ie Dnp3](https://www.precursorintelligence.com/product/siemens/tim_4r-ie_dnp3) by [Siemens](https://www.precursorintelligence.com/vendors/siemens) (Hardware): version not specified - [Tim 4r-Ie Dnp3 Firmware](https://www.precursorintelligence.com/product/siemens/tim_4r-ie_dnp3_firmware) by [Siemens](https://www.precursorintelligence.com/vendors/siemens) (Operating system): before 3.3 - [Tim 4r-Ie Firmware](https://www.precursorintelligence.com/product/siemens/tim_4r-ie_firmware) by [Siemens](https://www.precursorintelligence.com/vendors/siemens) (Operating system): before 3.3 ## How do I fix CVE-2019-10939? 1. **Check whether you run it.** Compare your versions with the affected products above. Not sure what you run? Precursor Intelligence can work it out from your public website, or you can pick it from a list. 2. **Apply the vendor’s fix.** Install the update named in the vendor’s advisory. We’ve put the advisory first in the list. 3. **If you can’t patch today.** Follow any mitigation the vendor publishes, and limit who can reach the affected system from the internet until the update is in. 4. **Keep an eye on it.** Track the product and we tell you as soon as we spot this flaw on the list of exploited flaws, or a jump in its exploit likelihood. ### References - [cert-portal.siemens.com](https://cert-portal.siemens.com/productcert/pdf/ssa-359303.pdf) (Vendor advisory) ## Questions ### What is CVE-2019-10939? CVE-2019-10939 is a critical-severity flaw in Tim 3v-Ie from Siemens, published on 14 April 2020. It can be attacked from anywhere on the internet without logging in, and nobody has to click anything. If it works, the attacker can read data, change data and take it offline. ### How serious is CVE-2019-10939? It scores 9.8 out of 10 on the CVSS severity scale, which is critical. Our risk score for CVE-2019-10939 is 54 out of 100, which is Medium. Its action is "Plan remediation". Not confirmed as exploited yet, but serious or likely enough that it should not wait for a quiet month. ### Is CVE-2019-10939 being exploited? It is not on the list of flaws known to be exploited today. The latest forecast puts the chance of it being used in the next 30 days at 1.1%. That can change at any time, which is why we keep watching. ### Which versions does CVE-2019-10939 affect? For Tim 3v-Ie from Siemens: version not specified. The record lists 10 products in all, each with its versions, under "Who is affected" on this page. ### How do I fix CVE-2019-10939? Install the update the vendor names in its advisory, linked first under "How do I fix" on this page. If you can't patch today, follow the vendor's mitigation and limit who can reach the affected system from the internet. ## Does CVE-2019-10939 affect you? Precursor Intelligence keeps checking for you: - **Tell us what you run.** Pick your software from a list, or let us work it out from your website. - **We match it to every flaw.** Over 400,000 published flaws, checked against your list. - **Ranked by real-world risk.** Every flaw gets a 0 to 100 risk score, kept up to date, led by evidence criminals are using it. - **Told as soon as we know.** An alert by email, in the app or by webhook to your own tools. Start free (no card, nothing to install): https://www.precursorintelligence.com/register Book a demo: https://www.precursorintelligence.com/contact