CVE-2023-5366: Openvswitch don't match packets on nd_target field
CSIRTS triage
- What
- Open vSwitch fails to match packets on the nd_target field in neighbor discovery, bypassing intended filtering.
- Who is affected
- Open vSwitch deployments using nd_target field in flow rules for IPv6 neighbor discovery filtering.
- Urgency
- High severity (CVSS 7.1) bypass of packet filtering rules; allows unintended traffic to pass through switches.
- Action
- Upgrade Open vSwitch to patched version that correctly matches nd_target field in packet flows.
AI-assisted analysis generated from the source advisory — verify against the original.
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Details
Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2023-5366
Exploitation outlook
EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.
- Low exploitation riskCVE-2023-53660.39% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 32% of all EPSS-scored CVEs.
Referenced CVEs
| CVE | CSIRTS overview | External |
|---|---|---|
| CVE-2023-5366 | coverage & exploitation status | NVD · CVE.org |
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