# What is CVE-2018-4844? > CVE-2018-4844 is a medium-severity flaw (CVSS 6.7) in Simatic Wincc Oa UI from Siemens, published on 20 March 2018. 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 0.4%. If you run an affected version, plan in the vendor’s fix. Canonical page: https://www.precursorintelligence.com/what-is/cve-2018-4844 ## At a glance - **Verdict:** Plan it in. No sign of exploitation and a low forecast. Patch it in your normal update cycle. - **Precursor Intelligence risk score:** 20 out of 100 (Low); action: Monitor. Kept up to date as the evidence changes. - **Severity:** Medium (CVSS 6.7 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:** 0.4% (latest exploit-likelihood forecast) - **Published:** 20 March 2018 - **Record last updated:** 24 March 2023 - **Main product:** Simatic Wincc Oa UI from Siemens - **Affected products:** 1 ## What is CVE-2018-4844? In plain terms An attacker has to be on the same local network with an ordinary user account, but a person has to take an action first. If it works, the attacker can read data and change data. ### The official description A vulnerability has been identified in SIMATIC WinCC OA UI for Android (All versions < V3.15.10), SIMATIC WinCC OA UI for iOS (All versions < V3.15.10). Insufficient limitation of CONTROL script capabilities could allow read and write access from one HMI project cache folder to other HMI project cache folders within the app's sandbox on the same mobile device. This includes HMI project cache folders of other configured WinCC OA servers. The security vulnerability could be exploited by an attacker who tricks an app user to connect to an attacker-controlled WinCC OA server. Successful exploitation requires user interaction and read/write access to the app's folder on a mobile device. The vulnerability could allow reading data from and writing data to the app's folder. At the time of advisory publication no public exploitation of this security vulnerability was known. Siemens confirms the security vulnerability and provides mitigations to resolve the security issue. ### What kind of flaw is it? - CWE-269: Improper Privilege Management - CWE-284: Improper Access Control ### How an attack on it works - Where an attacker can be: On the same local network - How hard it is to pull off: Easy: no special conditions - Login needed first: An ordinary user account - Does someone have to click: Yes, a person has to take an action - What an attacker gets: Can read data and change data Severity vector: `CVSS:3.1/AV:A/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:N` ## Is CVE-2018-4844 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 0.4%. That can change at any time, which is why we keep watching. Exploit likelihood over the last 7 days: 0.4%, 0.4%, 0.4%, 0.4%, 0.4%, 0.4%, 0.4%. ### Timeline - 20 March 2018: Published - 24 March 2023: Record last updated ### How Precursor Intelligence ranks it CVE-2018-4844 scores **20 out of 100 (Low)**, with the action "Monitor". 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-2018-4844? The published record lists 1 product. Versions are as published: "before 3.15.10" means every version up to, but not including, 3.15.10. - [Simatic Wincc Oa UI](https://www.precursorintelligence.com/product/siemens/simatic_wincc_oa_ui) by [Siemens](https://www.precursorintelligence.com/vendors/siemens) (Application): before 3.15.10 ## How do I fix CVE-2018-4844? 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-822928.pdf) (Vendor advisory) - [securityfocus.com](http://www.securityfocus.com/bid/103475) (Broken link, Third-party advisory, Vulnerability database) - [ics-cert.us-cert.gov](https://ics-cert.us-cert.gov/advisories/ICSA-18-081-01) (Third-party advisory, Government resource, Vulnerability database) ## Questions ### What is CVE-2018-4844? CVE-2018-4844 is a medium-severity flaw in Simatic Wincc Oa UI from Siemens, published on 20 March 2018. An attacker has to be on the same local network with an ordinary user account, but a person has to take an action first. If it works, the attacker can read data and change data. ### How serious is CVE-2018-4844? It scores 6.7 out of 10 on the CVSS severity scale, which is medium. Our risk score for CVE-2018-4844 is 20 out of 100, which is Low. Its action is "Monitor". No sign of exploitation and a low forecast. Patch it in your normal update cycle. ### Is CVE-2018-4844 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 0.4%. That can change at any time, which is why we keep watching. ### Which versions does CVE-2018-4844 affect? For Simatic Wincc Oa UI from Siemens: before 3.15.10. ### How do I fix CVE-2018-4844? 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-2018-4844 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