CVE-2021-1243
No exploitation reported by the sources we read.
- Published2021-02-04
- Fixed in7.0.2 · 6.6.4
- WeaknessCWE-284
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
A vulnerability in the Local Packet Transport Services (LPTS) programming of the SNMP with the management plane protection feature of Cisco IOS XR Software could allow an unauthenticated, remote attacker to allow connections despite the management plane protection that is configured to deny access to the SNMP server of an affected device. This vulnerability is due to incorrect LPTS programming when using SNMP with management plane protection. An attacker could exploit this vulnerability by connecting to an affected device using SNMP. A successful exploit could allow the attacker to connect to the device on the configured SNMP ports. Valid credentials are required to execute any of the SNMP requests.
Timeline
dates in UTC- 2021-02-0417:15CVE 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-2021-1243?format=txt
- CSV export: https://api.ismalicious.com/edl/cve/CVE-2021-1243?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 |
|---|---|---|---|
| 7.0 | ≥ 7.0.0, < 7.0.2 | 7.0.2 | NVD |
| 6.x | > 6.1.1, < 6.6.4 | 6.6.4 | NVD |
| 6.7 | = 6.7.1 | no fix published | NVD |
| 7.0 | = 7.0.11 | no fix published | NVD |
| 7.1 | = 7.1.0 | no fix published | NVD |
| 7.2 | = 7.2.0 | no fix published | NVD |
as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.
Fix
- Update Cisco ios xr to 7.0.2 · 6.6.4
Advisories and patches
- tools.cisco.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
Technical details
- CVSS v3 Vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
- Published
- 2021-02-04
- Last Modified
- 2026-06-17
- NVD status
- Modified
Frequently asked questions
What is CVE-2021-1243?
Is CVE-2021-1243 actively exploited?
What is the CVSS score for CVE-2021-1243?
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Related vulnerabilities
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