5.8

CVE-2026-20038: cisco cisco nx-os system software in aci mode Improper Access Control

CVSS: 5.8v3.1MediumAwaiting analysis
Published 07-10-2026Last modified 07-10-2026
Open JSON

Vulnerability summary

CVE-2026-20038 is a medium (CVSS 5.8) Improper Access Control vulnerability in cisco cisco nx-os system software in aci mode. EPSS estimates a 0.30% chance of exploitation in the next 30 days, higher than 21.3% of scored vulnerabilities.

Overall risk
23/100
0100
Low · default modelHow is this calculated?
CVSS score
5.8/10
010
Medium · v3.1 (CVE.org)
EPSS score
0.30%
0%100%
Low · Change unavailable
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 07-10-2026
    PublishedVulnerability first disclosed.
  2. 07-10-2026
    Last modifiedVulnerability information updated.

Description

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.

CVSS metrics

2 scores · 2 sources · 1 version

EPSS trend

Probability

0.30%

Chance of exploitation in the next 30 days

Percentile

21%

Versus all other CVEs

30-day change

Change unavailable

Change unavailable

08-10-202618-10-2026
EPSS score
0.30%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Cisco1 product
  • cisco 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)

1 vendor · 1 product

References

1 links