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TI-2018-00140 Aliases CVE-2018-0173GHSA-pp38-rv9h-g7rc

Improper input validation in Cisco IOS and IOS XE

Priority CRITICAL 96Exploited in the wildCWE-20Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
None · None · High
Fix status
No fix listed

Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA.

Summary

A vulnerability in the Cisco IOS Software and Cisco IOS XE Software function that restores encapsulated option 82 information in DHCP Version 4 (DHCPv4) packets could allow an unauthenticated, remote attacker to cause an affected device to reload, resulting in a Relay Reply denial of service (DoS) condition. The vulnerability exists because the affected software performs incomplete input validation of encapsulated option 82 information that it receives in DHCPOFFER messages from DHCPv4 servers. An attacker could exploit this vulnerability by sending a crafted DHCPv4 packet to an affected device, which the device would then forward to a DHCPv4 server. When the affected software processes the option 82 information that is encapsulated in the response from the server, an error could occur. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a DoS condition. Cisco Bug IDs: CSCvg62754.

Why it matters now

Exploitation Active In CISA KEV since 2022-03-03CISA due date 2022-03-17
EPSS 0.07608 94th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Active
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
—Cisco IOS and IOS XECisco IOS and IOS XE—No fix listedCNA
  • Cisco IOS and IOS XE Vendor— Affected Cisco IOS and IOS XE Fixed in — No fix listed CNA

CPE configurations NVD · 24

CPEVersionsRoleVendor
cpe:2.3:o:cisco:ios:denali-16.3.4:*:*:*:*:*:*:*denali-16.3.4VulnerableCisco
cpe:2.3:o:cisco:ios_xe:denali-16.3.4:*:*:*:*:*:*:*denali-16.3.4VulnerableCisco
cpe:2.3:h:cisco:4321_integrated_services_router:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:h:cisco:4331_integrated_services_router:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:h:cisco:4351_integrated_services_router:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:h:cisco:4431_integrated_services_router:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:h:cisco:4451-x_integrated_services_router:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:h:cisco:asr_1000_series_route_processor_\(rp2\):-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:h:cisco:asr_1000_series_route_processor_\(rp3\):-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:h:cisco:asr_1001-hx:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
  • cpe:2.3:o:cisco:ios:denali-16.3.4:*:*:*:*:*:*:* Versions denali-16.3.4 Vulnerable ·Cisco
  • cpe:2.3:o:cisco:ios_xe:denali-16.3.4:*:*:*:*:*:*:* Versions denali-16.3.4 Vulnerable ·Cisco
  • cpe:2.3:h:cisco:4321_integrated_services_router:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:h:cisco:4331_integrated_services_router:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:h:cisco:4351_integrated_services_router:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:h:cisco:4431_integrated_services_router:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:h:cisco:4451-x_integrated_services_router:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:h:cisco:asr_1000_series_route_processor_\(rp2\):-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:h:cisco:asr_1000_series_route_processor_\(rp3\):-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:h:cisco:asr_1001-hx:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
Show 14 more CPE
CPEVersionsRoleVendor
cpe:2.3:h:cisco:asr_1001-x:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:h:cisco:asr_1002-hx:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:h:cisco:asr_1002-x:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:h:cisco:cloud_services_router_1000v:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:o:cisco:ios:*:*:*:*:*:*:*:*up to 15.2\(6\)e0aVulnerableCisco
cpe:2.3:o:cisco:ios_xe:*:*:*:*:*:*:*:*up to 15.2\(6\)e0aVulnerableCisco
cpe:2.3:h:rockwellautomation:allen-bradley_armorstratix_5700:-:*:*:*:*:*:*:*not specified by NVDRunning onRockwell
cpe:2.3:h:rockwellautomation:allen-bradley_stratix_5400:-:*:*:*:*:*:*:*not specified by NVDRunning onRockwell
cpe:2.3:h:rockwellautomation:allen-bradley_stratix_5410:-:*:*:*:*:*:*:*not specified by NVDRunning onRockwell
cpe:2.3:h:rockwellautomation:allen-bradley_stratix_5700:-:*:*:*:*:*:*:*not specified by NVDRunning onRockwell
cpe:2.3:h:rockwellautomation:allen-bradley_stratix_8000:-:*:*:*:*:*:*:*not specified by NVDRunning onRockwell
cpe:2.3:o:cisco:ios:*:*:*:*:*:*:*:*up to 15.2\(4a\)ea5VulnerableCisco
cpe:2.3:o:cisco:ios_xe:*:*:*:*:*:*:*:*up to 15.2\(4a\)ea5VulnerableCisco
cpe:2.3:h:rockwellautomation:allen-bradley_stratix_8300:-:*:*:*:*:*:*:*not specified by NVDRunning onRockwell
  • cpe:2.3:h:cisco:asr_1001-x:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:h:cisco:asr_1002-hx:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:h:cisco:asr_1002-x:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:h:cisco:cloud_services_router_1000v:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:o:cisco:ios:*:*:*:*:*:*:*:* Versions up to 15.2\(6\)e0a Vulnerable ·Cisco
  • cpe:2.3:o:cisco:ios_xe:*:*:*:*:*:*:*:* Versions up to 15.2\(6\)e0a Vulnerable ·Cisco
  • cpe:2.3:h:rockwellautomation:allen-bradley_armorstratix_5700:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Rockwell
  • cpe:2.3:h:rockwellautomation:allen-bradley_stratix_5400:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Rockwell
  • cpe:2.3:h:rockwellautomation:allen-bradley_stratix_5410:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Rockwell
  • cpe:2.3:h:rockwellautomation:allen-bradley_stratix_5700:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Rockwell
  • cpe:2.3:h:rockwellautomation:allen-bradley_stratix_8000:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Rockwell
  • cpe:2.3:o:cisco:ios:*:*:*:*:*:*:*:* Versions up to 15.2\(4a\)ea5 Vulnerable ·Cisco
  • cpe:2.3:o:cisco:ios_xe:*:*:*:*:*:*:*:* Versions up to 15.2\(4a\)ea5 Vulnerable ·Cisco
  • cpe:2.3:h:rockwellautomation:allen-bradley_stratix_8300:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Rockwell

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2022-03-03 Added to CISA KEV
  2. 2026-10-02 Threatist record created from CVE-2018-0173
  3. 2026-10-03 Alias added: GHSA-pp38-rv9h-g7rc

References

Advisory 4

  • TI-2018-00138 Improper input validation in Cisco IOS and IOS XE KEVCVSS 3.1CRITICAL 9.8
  • TI-2017-09019 Improper input validation in Cisco IOS and IOS XE KEVCVSS 3.1CRITICAL 9.8
  • TI-2017-02977 Improper input validation in Cisco IOS and IOS XE Software KEVCVSS 3.1CRITICAL 9.8
  • TI-2018-00135 Memory corruption in Cisco IOS, IOS XE, and IOS XR KEVCVSS 3.1HIGH 8.8
  • TI-2017-04499 Memory corruption in Cisco IOS KEVCVSS 3.1HIGH 8.8
  • TI-2017-04498 Memory corruption in Cisco IOS KEVCVSS 3.1HIGH 8.8
See all 617 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences