No exploitation reportedFix available

CVE-2020-15796

No exploitation reported by the sources we read.

Published2020-12-14
WeaknessCWE-248

Am I affected?

With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.

Description

A vulnerability has been identified in SIMATIC ET 200SP Open Controller (incl. SIPLUS variants) (V20.8), SIMATIC S7-1500 Software Controller (V20.8). The web server of the affected products contains a vulnerability that could allow a remote attacker to trigger a denial-of-service condition by sending a specially crafted HTTP request.

Timeline

dates in UTC

2020-12-1421:15CVE publishedNVD

Observed activity

isMalicious corpus · updated 2026-10-23 21:37 UTC

Indicators tagged with this CVE, per day0 indicators over 7 days

Block these indicators

Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2020-15796?format=txt
CSV export: https://api.ismalicious.com/edl/cve/CVE-2020-15796?format=csv
TAXII collection of exploited CVEs
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Versions per branch

NVD

Siemens simatic et 200sp open controller firmwareversion to verify

Branch	Affected	Fixed in	Source
20.8	≤ 20.8	no fix published	NVD

Siemens simatic s7-1500 software controller firmwareversion to verify

Branch	Affected	Fixed in	Source
20.8	≤ 20.8	no fix published	NVD

as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.

Distribution builds and vendor advisories

Packages from OSV.dev and products from the vendors' CSAF advisories.

version not verifiedVersions not verified: read as OSV.dev and the vendors publish them, not checked against each vendor's release list.

Vendor advisories

ICSA-20-343-09 CISA2 known affected
Siemens SIMATIC Controller Web Servers
SIMATIC ET 200SP Open Controller (incl. SIPLUS variants): V20.8 · SIMATIC S7-1500 Software Controller: V20.8

Full record on NVD

Fix

Vendor fix CISA ICSA-20-343-09 · 2 productsIf the PC Station web server does not restart automatically Windows reboot is required. This can be done while the control system is running as the PLC control functionality is not affected.
Vendor fix CISA ICSA-20-343-09 · 1 productUpdate to V21.8 - Download: https://support.industry.siemens.com/cs/us/en/view/109759122
Vendor fix CISA ICSA-20-343-09 · 1 productUpdate to V21.8 - Download: https://support.industry.siemens.com/cs/us/en/view/109478528
Mitigation from the vendor CISA ICSA-20-343-09 · 2 productsAs a general security measure, Siemens strongly recommends to protect network access to devices with appropriate mechanisms. In order to operate the devices in a protected IT environment, Siemens recommends to configure the environment according to Siemens' operational guidelines for Industrial Sec…

Advisories and patches

cert-portal.siemens.comVendor Advisory

Detection

Nuclei template: none so far
Exploit-DB: no entry
Proof-of-concept repositories: none listed

Sources

NVDCVSS 3.17.5read 2026-10-23
NVDCVSS 2.05read 2026-10-23
CNAweakness (CWE)CWE-248read 2026-10-23
FIRST EPSSEPSS score1.6 %2026-10-22

Technical details

CVSS v3 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Published: 2020-12-14
Last Modified: 2026-06-17
NVD status: Modified

Frequently asked questions

What is CVE-2020-15796?

Is CVE-2020-15796 actively exploited?

Active exploitation of CVE-2020-15796 has not been confirmed. Its EPSS score was 1.6% on 2026-10-22, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2020-15796?

CVE-2020-15796 has a CVSS v3 base score of 7.5 (HIGH severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

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