CVE-2020-28393
No exploitation reported by the sources we read.
- Published2021-05-12
- Fixed in6.4
- WeaknessCWE-682
Am I affected?
Debian, Ubuntu or Red Hat sometimes backport a fix without changing the upstream version number: such a version reads « to verify », never « 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
An unauthenticated remote attacker could create a permanent denial-of-service condition by sending specially crafted OSPF packets. Successful exploitation requires OSPF to be enabled on an affected device on the SCALANCE XM-400, XR-500 (All versions prior to v6.4).
Timeline
dates in UTC- 2021-05-1214:15CVE publishedNVD
Observed activity
isMalicious corpus · updated 2026-10-23 21:37 UTCBlock these indicators
- Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2020-28393?format=txt
- CSV export: https://api.ismalicious.com/edl/cve/CVE-2020-28393?format=csv
- TAXII collection of exploited CVEs
- The EDL and CSV take an API key on the Pro plan.
Versions per branch
NVD| Branch | Affected | Fixed in | Source |
|---|---|---|---|
| 6.4 | < 6.4 | 6.4 | NVD |
| Branch | Affected | Fixed in | Source |
|---|---|---|---|
| 6.4 | < 6.4 | 6.4 | NVD |
| Branch | Affected | Fixed in | Source |
|---|---|---|---|
| 6.4 | < 6.4 | 6.4 | NVD |
8 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
Siemens SCALANCE XM-400 and XR-500 Devices
SCALANCE XM-400 Family · SCALANCE XR-500 Family
Fix
- Update Siemens scalance xm-400 firmware to 6.4
- Vendor fix CISA ICSA-21-131-10 · 1 productUpdate to V6.4 or later version
- Mitigation from the vendor CISA ICSA-21-131-10 · 2 productsDisable OSPF in the layer 3 configuration menu (note that OSPF is disabled by default). The vulnerability is not exploitable, when OSPF is disabled.
- Mitigation from the vendor CISA ICSA-21-131-10 · 2 productsIf OSPF is used, set a password for the OSPF interface and enable MD5 authentication
Advisories and patches
- cert-portal.siemens.comVendor Advisory
Detection
- Nuclei template
- none so far ProjectDiscovery
- Exploit-DB
- no entry Exploit-DB
- Proof-of-concept repositories
- none listed PoC-in-GitHub
Sources
- NVDCVSS 3.17.5read 2026-10-23
- NVDCVSS 2.07.1read 2026-10-23
- CNAweakness (CWE)CWE-682read 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
- 2021-05-12
- Last Modified
- 2026-06-17
- NVD status
- Modified
Frequently asked questions
What is CVE-2020-28393?
Is CVE-2020-28393 actively exploited?
What is the CVSS score for CVE-2020-28393?
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