CVE-2021-21000
No exploitation reported by the sources we read.
- Published2021-05-24
- Fixed in03.06.19_\(18\)
- WeaknessCWE-770
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
On WAGO PFC200 devices in different firmware versions with special crafted packets an attacker with network access to the device could cause a denial of service for the login service of the runtime.
Timeline
dates in UTC- 2021-05-2411:15CVE publishedNVD
Observed activity
isMalicious corpus · updated 2026-10-23 18:48 UTCBlock these indicators
- Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2021-21000?format=txt
- CSV export: https://api.ismalicious.com/edl/cve/CVE-2021-21000?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 |
|---|---|---|---|
| 3.6 | < 03.06.19_\(18\) | 03.06.19_\(18\) | NVD |
| Branch | Affected | Fixed in | Source |
|---|---|---|---|
| 3.6 | < 03.06.19_\(18\) | 03.06.19_\(18\) | NVD |
| Branch | Affected | Fixed in | Source |
|---|---|---|---|
| 3.6 | < 03.06.19_\(18\) | 03.06.19_\(18\) | NVD |
24 more products in the sources.
as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.
Fix
- Update Wago 750-8202 firmware to 03.06.19_\(18\)
Detection
- Nuclei template
- none so far ProjectDiscovery
- Exploit-DB
- no entry Exploit-DB
- Proof-of-concept repositories
- none listed PoC-in-GitHub
Sources
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
- 2021-05-24
- Last Modified
- 2026-06-17
- NVD status
- Analyzed
Frequently asked questions
What is CVE-2021-21000?
Is CVE-2021-21000 actively exploited?
What is the CVSS score for CVE-2021-21000?
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