7.1

CVE-2026-55707: openstack neutron Incorrect Authorization

CVSS: 7.1v4.0HighDeferred
AliasesUBUNTU-CVE-2026-55707DEBIAN-CVE-2026-55707
Published 05-08-2026Last modified 12-08-2026
Open JSON

Vulnerability summary

CVE-2026-55707 is a high (CVSS 7.1) Incorrect Authorization vulnerability in openstack neutron. EPSS estimates a 0.43% chance of exploitation in the next 30 days, higher than 35.6% of scored vulnerabilities.

Overall risk
28/100
0100
Medium · default modelHow is this calculated?
CVSS score
7.1/10
010
High · v4.0 (CVE.org)
EPSS score
0.43%
0%100%
Low · +0.14 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 05-08-2026
    PublishedVulnerability first disclosed.
  2. 12-08-2026
    Last modifiedVulnerability information updated.

Description

In OpenStack Neutron before 28.0.2, the subnetpool onboarding API does not verify ownership of the target subnets. An authenticated user can onboard subnets from another project's shared network into their own subnetpool, mutating the victim's subnet state and altering L3 routing and address scope behavior for victim routers.

CVSS metrics

4 scores · 4 sources · 1 version

EPSS trend

Probability

0.43%

Chance of exploitation in the next 30 days

Percentile

36%

Versus all other CVEs

30-day change

+0.14 pp

From 0.28% on 19-09-2026

19-09-202619-10-2026
EPSS score
0.43%

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

Debian1 product
  • neutron< 2:21.0.0-7+deb12u1 | < 2:26.0.3-0+deb13u3 | < 2:28.0.1-2
Openstack1 product
  • neutron≥ 14.0.0, < 26.0.6 | ≥ 27.0.0, < 27.0.4 | ≥ 28.0.0, < 28.0.2
Ubuntu1 product
  • neutronAll versions (No fix recorded)

3 vendors · 3 products

References

9 links