CVE-2017-6740
Exploitation confirmed. First attested on 2022-03-03 by CISA-ADP, CISA KEV, GCVE · kevintel.
- Published2017-07-17
- WeaknessCWE-119
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
The Simple Network Management Protocol (SNMP) subsystem of Cisco IOS and IOS XE Software contains multiple vulnerabilities that could allow an authenticated, remote attacker to remotely execute code on an affected system or cause an affected system to reload. An attacker could exploit these vulnerabilities by sending a crafted SNMP packet to an affected system via IPv4 or IPv6. Only traffic directed to an affected system can be used to exploit these vulnerabilities. The vulnerabilities are due to a buffer overflow condition in the SNMP subsystem of the affected software. The vulnerabilities affect all versions of SNMP - Versions 1, 2c, and 3. To exploit these vulnerabilities via SNMP Version 2c or earlier, the attacker must know the SNMP read-only community string for the affected system. To exploit these vulnerabilities via SNMP Version 3, the attacker must have user credentials for the affected system. A successful exploit could allow the attacker to execute arbitrary code and obtain full control of the affected system or cause the affected system to reload. Customers are advised to apply the workaround as contained in the Workarounds section below. Fixed software information is available via the Cisco IOS Software Checker. All devices that have enabled SNMP and have not explicitly excluded the affected MIBs or OIDs should be considered vulnerable. There are workarounds that address these vulnerabilities.
Timeline
dates in UTCObserved activity
isMalicious corpus · updated 2026-10-23 18:48 UTCBlock these indicators
- Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2017-6740?format=txt
- CSV export: https://api.ismalicious.com/edl/cve/CVE-2017-6740?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 |
|---|---|---|---|
| 12.x | ≥ 12.0, ≤ 12.4 | no fix published | NVD |
| 15.x | ≥ 15.0, ≤ 15.6 | no fix published | NVD |
| Branch | Affected | Fixed in | Source |
|---|---|---|---|
| 3.17 | ≥ 2.2.0, ≤ 3.17 | no fix published | NVD |
as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.
Fix
- CISA’s required action: Apply updates per vendor instructions.due 2022-03-24
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
CISA Known Exploited Vulnerability
- Date Added
- 2022-03-03
- Patch Due Date
- 2022-03-24
- Ransomware Use
- Unknown
- Required Action
- Apply updates per vendor instructions.
Sources
- CISA KEVKEV entry2022-03-03
- GCVEexploitation2022-03-03
- CISA-ADPSSVC decisionactive2024-11-08
- OpenCVESSVC decisionactive—
- NVDCVSS 3.18.8read 2026-10-23
- CNACVSS 3.08.8read 2026-10-23
- NVDCVSS 2.09read 2026-10-23
- CNAweakness (CWE)CWE-119read 2026-10-23
- NVDweakness (CWE)CWE-119read 2026-10-23
- FIRST EPSSEPSS score11.1 %read 2026-10-23
Technical details
- CVSS v3 Vector
- CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- Published
- 2017-07-17
- Last Modified
- 2026-06-17
- NVD status
- Analyzed
Frequently asked questions
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Related vulnerabilities
Same product first, then the same vendor advisory and the same publication week.