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TI-2026-69206 Aliases CVE-2026-20038GHSA-8r87-mj76-xw8h

EPG contract bypass in Cisco NX-OS System Software in ACI Mode

Priority LOW 32CWE-284Published · Updated

Key facts

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

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-284.

Summary

Cisco NX-OS System Software in ACI Mode on Cisco Nexus 9000 Series Fabric Switches is affected, with many listed releases starting at 15.2(1g). The endpoint group (EPG) contract functionality has improper access control (CWE-284). An unauthenticated remote attacker can send IPv4 or IPv6 UDP packets using DHCP ports through an affected device to bypass configured EPG contracts.

Written with Claude Haiku 5.5 from the sources below · 2026-10-29

Description from the CNA

A vulnerability in the endpoint group (EPG) contract functionality of Cisco Nexus 9000 Series Fabric Switches in ACI Mode could allow an unauthenticated, remote attacker to bypass configured EPG contracts. This vulnerability is due to an improper control with EPG contracts. An attacker could exploit this vulnerability by sending IPv4 or IPv6 packets using UDP source and destination ports that are assigned to DHCP traffic through an affected device. A successful exploit could allow the attacker to bypass EPG contracts on the affected device.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00301 23rd 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
Yes
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 NX-OS System Software in ACI Mode15.2(1g); 15.2(2e); 15.2(2f); 15.2(2g); 15.2(2h); 15.2(3f); 15.2(3e); 15.2(3g); 15.2(4d); 15.2(4e); 15.2(5c); 15.2(5d); 16.0(1g); 15.2(5e); 15.2(4f); 15.2(6e); 15.2(6h); 16.0(1j); 15.2(6g); 15.2(7f); 15.2(7g); 16.0(2h); 15.2(8d); 16.0(2j); 15.2(8e); 16.0(3d); 16.0(3e); 15.2(8f); 15.2(8g); 15.3(1d); 15.2(8h); 16.0(4c); 15.3(2a); 15.2(8i); 16.0(5h); 15.3(2b); 16.0(3g); 16.0(5j); 15.3(2c); 16.0(6c); 15.3(2d); 16.1(1f); 16.0(7e); 16.0(8e); 15.3(2e); 16.0(8f); 16.1(2f); 16.1(2g); 15.3(2f); 16.0(9c); 16.1(3f); 16.0(9d); 16.0(6h); 16.0(8h); 16.1(3g); 16.0(9e); 16.1(4h); 16.1(5e); 16.2(1g); 16.0(9f); 16.2(2e)—No fix listedCNA
  • Cisco NX-OS System Software in ACI Mode VendorCisco Affected 15.2(1g); 15.2(2e); 15.2(2f); 15.2(2g); 15.2(2h); 15.2(3f); 15.2(3e); 15.2(3g); 15.2(4d); 15.2(4e); 15.2(5c); 15.2(5d); 16.0(1g); 15.2(5e); 15.2(4f); 15.2(6e); 15.2(6h); 16.0(1j); 15.2(6g); 15.2(7f); 15.2(7g); 16.0(2h); 15.2(8d); 16.0(2j); 15.2(8e); 16.0(3d); 16.0(3e); 15.2(8f); 15.2(8g); 15.3(1d); 15.2(8h); 16.0(4c); 15.3(2a); 15.2(8i); 16.0(5h); 15.3(2b); 16.0(3g); 16.0(5j); 15.3(2c); 16.0(6c); 15.3(2d); 16.1(1f); 16.0(7e); 16.0(8e); 15.3(2e); 16.0(8f); 16.1(2f); 16.1(2g); 15.3(2f); 16.0(9c); 16.1(3f); 16.0(9d); 16.0(6h); 16.0(8h); 16.1(3g); 16.0(9e); 16.1(4h); 16.1(5e); 16.2(1g); 16.0(9f); 16.2(2e) Fixed in — No fix listed CNA

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:o:cisco:nx-os:*:*:*:*:*:*:*:*——Cisco
  • cpe:2.3:o:cisco:nx-os:*:*:*:*:*:*:*:* Versions — — ·Cisco

Remediation

The sources list no fixed version for Cisco NX-OS System Software in ACI Mode.

Written with Claude Haiku 5.5 from the sources below · 2026-10-29

Timeline

  1. 2026-10-07 Threatist record created from CVE-2026-20038
  2. 2026-10-07 CISA SSVC decision points changed
  3. 2026-10-07 Priority changed: MEDIUM → LOW
  4. 2026-10-07 Alias added: GHSA-8r87-mj76-xw8h

References

  • TI-2026-74174 Arbitrary file write in Cisco Secure Email Gateway via AMP feature KEVCVSS 3.1CRITICAL 9.8
  • TI-2026-53490 Cisco Catalyst SD-WAN Manager System Account Authorization Bypass Vulnerability KEVCVSS 3.1CRITICAL 9.8
  • TI-2026-53489 Cisco Secure Email Gateway SQL Injection Vulnerability KEVCVSS 3.1CRITICAL 9.8
  • TI-2026-53488 Cisco Identity Services Engine Authentication Bypass Vulnerability KEVCVSS 3.1CRITICAL 10.0
  • TI-2026-16388 Cisco Catalyst SD-WAN Controller Authentication Bypass Vulnerability KEVCVSS 3.1CRITICAL 10.0
  • TI-2026-16344 Cisco Secure Firewall Management Center Software Remote Code Execution Vulnerability KEVCVSS 3.1CRITICAL 10.0
See all 7059 →

Sources