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CVE-2017-6736

Cisco — Cisco IOS and IOS XE Software SNMP Remote Code Execution Vulnerability

Cisco · CWE-119 · in CISA KEV since 2022-03-03

KEV since 2022 · listed over a yearCISA KEVActively Exploited
78

EVRS 78 of 100 Urgent

Patch This Cycle

Rank 642 of 2,960 tracked

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Why it scores 78

Evidence available: 6 of 7 signals

Listed in the CISA KEV catalog, and an EPSS probability of 0.704.

  • CISA KEVApplied
  • RansomwareDid not apply
  • Vendor exploitationDid not apply
  • EPSSApplied
  • Microsoft Exploitability IndexNot applicable
  • Pre-patch disclosureNo data
  • KEV recencyDid not apply
  • CVSSApplied

The band answers “how soon”, not “how bad”. No data for: Pre-patch disclosure. Why some signals show no data

Fix

Patch or fixed version identified

CISA required action

Fixed in

ios: update to a version newer than 12.4 | ios: update to a version newer than 15.6 | ios xe: update to a version newer than 3.17

Affected versions

  • ios>= 12.0 <= 12.4>= 15.0 <= 15.6
  • ios xe>= 2.2.0 <= 3.17

Remediation

Apply updates per vendor instructions.

Fixed versions from NVD.

Evidence

Each value with its source
MeasureValueSource
CVSS base scoreHow severe the flaw is in itself. It does not say how likely an attack is. 8.8 NVD
FIRST EPSSFIRST's estimate of the chance this is exploited in the next 30 days, and how that ranks against all CVEs. 0.704 (99.39th pctl) FIRST EPSS
Actively exploitedWhether a source of record has confirmed attacks using it in the wild. Confirmed CISA KEV
Ransomware campaign useWhether CISA has seen ransomware operators use it. Unknown or none CISA KEV
CISA remediation deadlineThe date US federal agencies must have fixed or mitigated it. 2022-03-24 · KEV since 2022 · listed over a year CISA KEV
Public exploit moduleA module existing is not the same as active exploitation. None known Metasploit
EUVD cross-referenceENISA's record: CVSS 8.8 (v3.0), assigned by cisco. Listed ENISA EUVD

Description

NVD

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.

What CISA says to do