Security readout for executives and security teams
Plain-English summary
Cisco IOS and IOS XE devices with SNMP enabled can be compromised or forced to reload if an authenticated remote attacker sends a crafted SNMP packet. Because CISA lists CVE-2017-6743 in KEV, treat exposed or poorly governed SNMP on Cisco infrastructure as an urgent operational risk.
Executive priority
Prioritize remediation for internet-reachable, partner-reachable, or broadly internally reachable Cisco network devices. A successful compromise could give full control of routers or switches, and KEV status means this should be handled as an active-risk infrastructure issue, not routine patch backlog.
Technical view
The vulnerability is a buffer overflow in the Cisco IOS and IOS XE SNMP subsystem affecting SNMPv1, v2c, and v3. Exploitation requires the SNMP read-only community string for v1/v2c or valid SNMPv3 credentials. Successful exploitation can allow arbitrary code execution with full device control or device reload.
Likely exposure
Exposure is most likely on Cisco IOS or IOS XE devices with SNMP enabled that have not excluded the affected MIBs or OIDs and are reachable over IPv4 or IPv6 by someone with SNMP community strings or credentials.
Exploitation context
CISA KEV status supports active exploitation in the wild. The source bundle does not provide exploit details, affected MIB/OID names, or observed campaign context. Exploitation is authenticated and targets traffic directed at the affected device.
Researcher notes
Key constraints are authentication and device-directed SNMP traffic. The CVSS vector is network, low complexity, low privileges, no user interaction, with high confidentiality, integrity, and availability impact. Evidence supports Cisco IOS and IOS XE SNMP subsystem exposure; do not generalize beyond those products from this bundle.
Mitigation direction
- Use Cisco IOS Software Checker to identify fixed software for each affected device.
- Apply Cisco's documented workaround from the advisory where upgrades are delayed.
- Explicitly exclude affected MIBs or OIDs where Cisco guidance applies.
- Prioritize devices with SNMP enabled and management reachability over IPv4 or IPv6.
- Validate SNMP community strings and SNMPv3 credential governance during remediation.
Validation and detection
- Inventory Cisco IOS and IOS XE devices and record running software versions.
- Confirm whether SNMP is enabled on each device.
- Check whether affected MIBs or OIDs are explicitly excluded.
- Map which networks can send SNMP traffic to each device.
- Verify fixed software or Cisco workaround deployment after change windows.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-119: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupExecution behavior lookup
The CVE wording references code or command execution, so execution technique review may help defensive triage. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2017-6743 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- High
- CVSS
- 8.8 (3.0)
- Known Exploited
- Yes
- Published
Vector: CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CISA KEV status
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H2.85.9Primary CVE scoreVulnerability scoring details
Base CVSS 3.0 score
8.8HighVector: CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Source materials
- CVE List V5 sourceCVE List V5
- cisco-sa-20170629-snmpCVE reference
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20170629-snmpCVE reference · x_refsource_CONFIRM, x_transferred
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2017-6743CVE reference · government-resource
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Improper Restriction of Operations within the Bounds of a Memory Buffer
Improper Restriction of Operations within the Bounds of a Memory Buffer represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.