# What is CVE-2018-4843? > CVE-2018-4843 is a medium-severity flaw (CVSS 6.5) in Simatic Cp 343-1 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 0.5%. If you run an affected version, plan in the vendor’s fix. Canonical page: https://www.precursorintelligence.com/what-is/cve-2018-4843 ## 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:** 25 out of 100 (Low); action: Monitor. Kept up to date as the evidence changes. - **Severity:** Medium (CVSS 6.5 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:** 0.5% (latest exploit-likelihood forecast) - **Published:** 20 March 2018 - **Record last updated:** 9 May 2023 - **Main product:** Simatic Cp 343-1 from Siemens - **Affected products:** 22 ## What is CVE-2018-4843? In plain terms An attacker has to be on the same local network without logging in, and nobody has to click anything. If it works, the attacker can take it offline. ### The official description A vulnerability has been identified in SIMATIC S7-400 CPU 414-3 PN/DP V7 (All versions < V7.0.3), SIMATIC S7-400 CPU 414F-3 PN/DP V7 (All versions < V7.0.3), SIMATIC S7-400 CPU 416-3 PN/DP V7 (All versions < V7.0.3), SIMATIC S7-400 CPU 416F-3 PN/DP V7 (All versions < V7.0.3), SIMATIC CP 343-1 (incl. SIPLUS variants) (All versions), SIMATIC CP 343-1 Advanced (incl. SIPLUS variants) (All versions), SIMATIC CP 443-1 (All versions < V3.3), SIMATIC CP 443-1 (All versions < V3.3), SIMATIC CP 443-1 Advanced (All versions < V3.3), SIMATIC ET 200pro IM154-8 PN/DP CPU (All versions < V3.2.16), SIMATIC ET 200pro IM154-8F PN/DP CPU (All versions < V3.2.16), SIMATIC ET 200pro IM154-8FX PN/DP CPU (All versions < V3.2.16), SIMATIC ET 200S IM151-8 PN/DP CPU (All versions < V3.2.16), SIMATIC ET 200S IM151-8F PN/DP CPU (All versions < V3.2.16), SIMATIC S7-1500 CPU family (incl. related ET200 CPUs and SIPLUS variants) (All versions < V1.7.0), SIMATIC S7-1500 Software Controller (All versions < V1.7.0), SIMATIC S7-300 CPU 314C-2 PN/DP (All versions < V3.3.16), SIMATIC S7-300 CPU 315-2 PN/DP (All versions < V3.2.16), SIMATIC S7-300 CPU 315F-2 PN/DP (All versions < V3.2.16), SIMATIC S7-300 CPU 315T-3 PN/DP (All versions < V3.2.16), SIMATIC S7-300 CPU 317-2 PN/DP (All versions < V3.2.16), SIMATIC S7-300 CPU 317F-2 PN/DP (All versions < V3.2.16), SIMATIC S7-300 CPU 317T-3 PN/DP (All versions < V3.2.16), SIMATIC S7-300 CPU 317TF-3 PN/DP (All versions < V3.2.16), SIMATIC S7-300 CPU 319-3 PN/DP (All versions < V3.2.16), SIMATIC S7-300 CPU 319F-3 PN/DP (All versions < V3.2.16), SIMATIC S7-400 CPU 412-2 PN V7 (All versions < V7.0.3), SIMATIC S7-400 H V6 CPU family (incl. SIPLUS variants) (All versions < V6.0.9), SIMATIC S7-400 PN/DP V6 CPU family (incl. SIPLUS variants) (All versions < V6.0.7), SIMATIC S7-410 CPU family (incl. SIPLUS variants) (All versions < V8.1), SIMATIC WinAC RTX 2010 (All versions < V2010 SP3), SIMATIC WinAC RTX F 2010 (All versions < V2010 SP3), SINUMERIK 828D (All versions < V4.7 SP6 HF1), SIPLUS ET 200S IM151-8 PN/DP CPU (All versions < V3.2.16), SIPLUS ET 200S IM151-8F PN/DP CPU (All versions < V3.2.16), SIPLUS NET CP 443-1 (All versions < V3.3), SIPLUS NET CP 443-1 Advanced (All versions < V3.3), SIPLUS S7-300 CPU 314C-2 PN/DP (All versions < V3.3.16), SIPLUS S7-300 CPU 315-2 PN/DP (All versions < V3.2.16), SIPLUS S7-300 CPU 315F-2 PN/DP (All versions < V3.2.16), SIPLUS S7-300 CPU 317-2 PN/DP (All versions < V3.2.16), SIPLUS S7-300 CPU 317F-2 PN/DP (All versions < V3.2.16), SIPLUS S7-400 CPU 414-3 PN/DP V7 (All versions < V7.0.3), SIPLUS S7-400 CPU 416-3 PN/DP V7 (All versions < V7.0.3), Softnet PROFINET IO for PC-based Windows systems (All versions). Responding to a PROFINET DCP request with a specially crafted PROFINET DCP packet could cause a denial of service condition of the requesting system. The security vulnerability could be exploited by an attacker located on the same Ethernet segment (OSI Layer 2) as the targeted device. A manual restart is required to recover the system. ### What kind of flaw is it? - CWE-20: Improper Input Validation ### 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: No login needed - Does someone have to click: No, nobody has to do anything - What an attacker gets: Can take it offline Severity vector: `CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H` ## Is CVE-2018-4843 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 0.5%. That can change at any time, which is why we keep watching. Exploit likelihood over the last 7 days: 0.5%, 0.5%, 0.5%, 0.5%, 0.5%, 0.5%, 0.5%. ### Timeline - 20 March 2018: Published - 9 May 2023: Record last updated ### How Precursor Intelligence ranks it CVE-2018-4843 scores **25 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-2018-4843? The published record lists 22 products. Versions are as published: "before 1.7.0" means every version up to, but not including, 1.7.0. - [Simatic Cp 343-1](https://www.precursorintelligence.com/product/siemens/simatic_cp_343-1) by [Siemens](https://www.precursorintelligence.com/vendors/siemens) (Hardware): version not specified - [Simatic Cp 343-1 Firmware](https://www.precursorintelligence.com/product/siemens/simatic_cp_343-1_firmware) by [Siemens](https://www.precursorintelligence.com/vendors/siemens) (Operating system): version not specified - [Simatic Cp 443-1](https://www.precursorintelligence.com/product/siemens/simatic_cp_443-1) by [Siemens](https://www.precursorintelligence.com/vendors/siemens) (Hardware): version not specified - [Simatic Cp 443-1 Firmware](https://www.precursorintelligence.com/product/siemens/simatic_cp_443-1_firmware) by [Siemens](https://www.precursorintelligence.com/vendors/siemens) (Operating system): version not specified - [Simatic S7-1500](https://www.precursorintelligence.com/product/siemens/simatic_s7-1500) by [Siemens](https://www.precursorintelligence.com/vendors/siemens) (Hardware): version not specified - [Simatic S7-1500 Firmware](https://www.precursorintelligence.com/product/siemens/simatic_s7-1500_firmware) by [Siemens](https://www.precursorintelligence.com/vendors/siemens) (Operating system): before 1.7.0 - [Simatic S7-300](https://www.precursorintelligence.com/product/siemens/simatic_s7-300) by [Siemens](https://www.precursorintelligence.com/vendors/siemens) (Hardware): version not specified - [Simatic S7-300 Firmware](https://www.precursorintelligence.com/product/siemens/simatic_s7-300_firmware) by [Siemens](https://www.precursorintelligence.com/vendors/siemens) (Operating system): version not specified - [Simatic S7-400 H V6](https://www.precursorintelligence.com/product/siemens/simatic_s7-400_h_v6) by [Siemens](https://www.precursorintelligence.com/vendors/siemens) (Hardware): version not specified - [Simatic S7-400 H V6 Firmware](https://www.precursorintelligence.com/product/siemens/simatic_s7-400_h_v6_firmware) by [Siemens](https://www.precursorintelligence.com/vendors/siemens) (Operating system): version not specified - Simatic S7-400 Pn/dp V6 by [Siemens](https://www.precursorintelligence.com/vendors/siemens) (Hardware): version not specified - Simatic S7-400 Pn/dp V6 Firmware by [Siemens](https://www.precursorintelligence.com/vendors/siemens) (Operating system): before 6.0.7 - Simatic S7-400 Pn/dp V7 by [Siemens](https://www.precursorintelligence.com/vendors/siemens) (Hardware): version not specified - Simatic S7-400 Pn/dp V7 Firmware by [Siemens](https://www.precursorintelligence.com/vendors/siemens) (Operating system): version not specified - [Simatic S7-410](https://www.precursorintelligence.com/product/siemens/simatic_s7-410) by [Siemens](https://www.precursorintelligence.com/vendors/siemens) (Hardware): version not specified - [Simatic S7-410 Firmware](https://www.precursorintelligence.com/product/siemens/simatic_s7-410_firmware) by [Siemens](https://www.precursorintelligence.com/vendors/siemens) (Operating system): before 8.1 - [Simatic Winac Rtx 2010](https://www.precursorintelligence.com/product/siemens/simatic_winac_rtx_2010) by [Siemens](https://www.precursorintelligence.com/vendors/siemens) (Hardware): version not specified - [Simatic Winac Rtx 2010 Firmware](https://www.precursorintelligence.com/product/siemens/simatic_winac_rtx_2010_firmware) by [Siemens](https://www.precursorintelligence.com/vendors/siemens) (Operating system): version not specified - [Sinumerik 828d](https://www.precursorintelligence.com/product/siemens/sinumerik_828d) by [Siemens](https://www.precursorintelligence.com/vendors/siemens) (Hardware): version not specified - [Sinumerik 828d Firmware](https://www.precursorintelligence.com/product/siemens/sinumerik_828d_firmware) by [Siemens](https://www.precursorintelligence.com/vendors/siemens) (Operating system): version not specified - [Softnet Pn-Io Linux](https://www.precursorintelligence.com/product/siemens/softnet_pn-io_linux) by [Siemens](https://www.precursorintelligence.com/vendors/siemens) (Hardware): version not specified - [Softnet Pn-Io Linux Firmware](https://www.precursorintelligence.com/product/siemens/softnet_pn-io_linux_firmware) by [Siemens](https://www.precursorintelligence.com/vendors/siemens) (Operating system): version not specified ## How do I fix CVE-2018-4843? 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-592007.pdf) (Vendor advisory) ## Questions ### What is CVE-2018-4843? CVE-2018-4843 is a medium-severity flaw in Simatic Cp 343-1 from Siemens, published on 20 March 2018. An attacker has to be on the same local network without logging in, and nobody has to click anything. If it works, the attacker can take it offline. ### How serious is CVE-2018-4843? It scores 6.5 out of 10 on the CVSS severity scale, which is medium. Our risk score for CVE-2018-4843 is 25 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-2018-4843 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 0.5%. That can change at any time, which is why we keep watching. ### Which versions does CVE-2018-4843 affect? For Simatic Cp 343-1 from Siemens: version not specified. The record lists 22 products in all, each with its versions, under "Who is affected" on this page. ### How do I fix CVE-2018-4843? 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-2018-4843 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