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TI-2018-00435 Aliases CVE-2018-0476GHSA-72m2-hw7c-6c7r

Cisco IOS XE Software NAT Session Initiation Protocol Application Layer Gateway Denial of Service Vulnerability

Priority MEDIUM 41CWE-399Published · Updated

Key facts

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

Attack profile from CVSS 3.0 · NVD. Fix status from CNA. Impact type from CWE-399 and the CVSS impact.

Summary

A vulnerability in the Network Address Translation (NAT) Session Initiation Protocol (SIP) Application Layer Gateway (ALG) of Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause an affected device to reload. The vulnerability is due to improper processing of SIP packets in transit while NAT is performed on an affected device. An unauthenticated, remote attacker could exploit this vulnerability by sending crafted SIP packets via UDP port 5060 through an affected device that is performing NAT for SIP packets. A successful exploit could allow an attacker to cause the device to reload, resulting in a denial of service (DoS) condition.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.13698 96th 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
None
Automatable
No
Technical impact
Partial

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

Affected products

VendorProductAffected versionsFixed inStatusSource
CiscoCisco IOS XE Softwareall versions—No fix listedCNA
  • Cisco IOS XE Software VendorCisco Affected all versions Fixed in — No fix listed CNA

CPE configurations NVD · 3

CPEVersionsRoleVendor
cpe:2.3:o:cisco:ios_xe:15.5\(3\)s5.1:*:*:*:*:*:*:*15.5(3)s5.1VulnerableCisco
cpe:2.3:o:cisco:ios_xe:15.5\(3\)s6.1:*:*:*:*:*:*:*15.5(3)s6.1VulnerableCisco
cpe:2.3:o:cisco:ios_xe:16.6.2:*:*:*:*:*:*:*16.6.2VulnerableCisco
  • cpe:2.3:o:cisco:ios_xe:15.5\(3\)s5.1:*:*:*:*:*:*:* Versions 15.5(3)s5.1 Vulnerable ·Cisco
  • cpe:2.3:o:cisco:ios_xe:15.5\(3\)s6.1:*:*:*:*:*:*:* Versions 15.5(3)s6.1 Vulnerable ·Cisco
  • cpe:2.3:o:cisco:ios_xe:16.6.2:*:*:*:*:*:*:* Versions 16.6.2 Vulnerable ·Cisco

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2018-0476
  2. 2026-10-03 Alias added: GHSA-72m2-hw7c-6c7r

References

Advisory 1

  • TI-2023-06904 Cisco is providing an update for the ongoing investigation into observed exploitation of… KEVCVSS 3.1CRITICAL 10.0
  • TI-2018-00122 Memory corruption 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-2017-04498 Memory corruption in Cisco IOS KEVCVSS 3.1HIGH 8.8
  • TI-2017-04497 Memory corruption in Cisco IOS XE Software KEVCVSS 3.1HIGH 8.8
See all 561 →

Sources

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