No exploitation reportedFix available

CVE-2020-15800

Q: Is CVE-2020-15800 actively exploited?

Active exploitation of CVE-2020-15800 has not been confirmed. Its EPSS score was 1.7% on 2026-10-22, the estimated probability of exploitation in the next 30 days.

Q: What is the CVSS score for CVE-2020-15800?

CVE-2020-15800 has a CVSS v3 base score of 9.8 (CRITICAL severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

No exploitation reported by the sources we read.

Published2021-01-12
Fixed in5.5.0
WeaknessCWE-122 · CWE-787

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 SCALANCE X-200 switch family (incl. SIPLUS NET variants) (All versions < V5.2.5), SCALANCE X-200IRT switch family (incl. SIPLUS NET variants) (All versions < V5.5.0), SCALANCE X-300 switch family (incl. X408 and SIPLUS NET variants) (All versions < V4.1.0). The webserver of the affected devices contains a vulnerability that may lead to a heap overflow condition. An attacker could cause this condition on the webserver by sending specially crafted requests. This could stop the webserver temporarily.

Timeline

dates in UTC

2021-01-1221:15CVE publishedNVD

Observed activity

isMalicious corpus · updated 2026-10-23 18:48 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-2020-15800?format=txt
CSV export: https://api.ismalicious.com/edl/cve/CVE-2020-15800?format=csv
TAXII collection of exploited CVEs
The EDL and CSV take an API key on the Pro plan.

Versions per branch

NVD

Siemens scalance x200-4pirt firmwareversion to verify

Branch	Affected	Fixed in	Source
5.5	< 5.5.0	5.5.0	NVD

Siemens scalance x201-3pirt firmwareversion to verify

Branch	Affected	Fixed in	Source
5.5	< 5.5.0	5.5.0	NVD

Siemens scalance x202-2irt firmwareversion to verify

Branch	Affected	Fixed in	Source
5.5	< 5.5.0	5.5.0	NVD

63 more products in the sources.

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-21-012-05 CISA3 known affected
Siemens SCALANCE X Products (Update B)
SCALANCE X-200 switch family (incl. SIPLUS NET variants) · SCALANCE X-200IRT switch family (incl. SIPLUS NET variants) · SCALANCE X-300 switch family (incl. X408 and SIPLUS NET variants)

Full record on NVD

Fix

Update Siemens scalance x200-4pirt firmware to 5.5.0
Vendor fix CISA ICSA-21-012-05 · 1 productUpdate to V5.2.5 or later version
Vendor fix CISA ICSA-21-012-05 · 1 productUpdate to V5.5.0 or later version
Vendor fix CISA ICSA-21-012-05 · 1 productUpdate to V4.1.0 or later version
Mitigation from the vendor CISA ICSA-21-012-05 · 3 productsLimit network traffic of web servers of Scalance X switches to trusted connections by firewall rules (port 443/tcp).

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 3.19.8read 2026-10-23
NVDCVSS 2.09.3read 2026-10-23
CNAweakness (CWE)CWE-122read 2026-10-23
NVDweakness (CWE)CWE-787read 2026-10-23
FIRST EPSSEPSS score1.7 %2026-10-22

Technical details

CVSS v3 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Published: 2021-01-12
Last Modified: 2026-06-17
NVD status: Modified

Frequently asked questions

What is CVE-2020-15800?

Is CVE-2020-15800 actively exploited?

Active exploitation of CVE-2020-15800 has not been confirmed. Its EPSS score was 1.7% on 2026-10-22, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2020-15800?

CVE-2020-15800 has a CVSS v3 base score of 9.8 (CRITICAL severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

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