Auth bypass in OpenStack Neutron

CVE-2026-49299

In OpenStack Neutron before 28.0.1, the tagging controller enforces plural policy action names on single-tag write operations while the defined policy rules use singular names. The mismatched names evaluate as allowed under the default policy, permitting a project reader to create and update tags on same-project resources. Deployments running Neutron 26.0.0 or later are affected.

Vulnerability class: Broken Access Control

Published · last modified .

EPSS exploit prediction

EPSS: 0.004 (35.6th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 36th percentile — 35.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-49299: held from 0.003 to 0.004.

EPSS over last 30 days · oldest: 0.003 · newest: 0.004 · change: +0.001

Affected products

Weakness classification (CWE)

References