Security readout for executives and security teams
Plain-English summary
This vulnerability lets a user who controls a cloud server instance pretend to have another system's hardware address on certain OpenStack Neutron virtual networks. The main business risk is disruption of tenant networking, with possible traffic interception in some cases.
Executive priority
Prioritize remediation for multi-tenant OpenStack environments or clouds hosting untrusted workloads. Single-tenant or non-linuxbridge deployments have lower apparent urgency, but should still verify configuration.
Technical view
CVE-2021-38598 affects OpenStack Neutron before 16.4.1, 17.x before 17.1.3, and 18.0.0 when linuxbridge uses ebtables-nft on a Netfilter-based platform. Crafted packets from an attached instance can bypass intended hardware address controls, enabling address impersonation.
Likely exposure
Exposure appears limited to OpenStack Neutron deployments using the linuxbridge driver with ebtables-nft on Netfilter-based platforms, on the affected version ranges named in the CVE record.
Exploitation context
The source bundle does not show KEV listing, public exploitation, CVSS, or CWE data. The attacker must control a server instance connected to the virtual switch; impact is denial of service or possible traffic interception.
Researcher notes
The affected condition is specific: Neutron version plus linuxbridge plus ebtables-nft on Netfilter. The public bundle names impact but lacks scoring and detailed advisory context, so validation should focus on configuration matching.
Mitigation direction
- Upgrade Neutron to 16.4.1, 17.1.3, or a later fixed release.
- Confirm whether linuxbridge with ebtables-nft is used in production.
- Review OpenStack vendor guidance for supported backports or platform-specific advisories.
- Reduce exposure of untrusted tenant instances until affected hosts are remediated.
Validation and detection
- Inventory OpenStack Neutron versions across controllers and network nodes.
- Check whether linuxbridge is configured as the active Neutron driver.
- Verify whether ebtables-nft is present on Netfilter-based hosts.
- Confirm remediation by matching deployed versions against fixed version thresholds.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CVE-2021-38598 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Unknown
- CVSS
- Not scored
- Known Exploited
- No
- Published
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS and timeline data
No CVSS vectors or timeline events were available in the normalized CVE source material.
Source materials
- CVE List V5 sourceCVE List V5
- https://launchpad.net/bugs/1938670CVE reference · x_refsource_MISC
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.